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Find the probability of a number of successes or failures in a binomial experiment using a tree diagram, a bar graph, and direct calculation.

Randomly throw darts at a target and see what percent are "hits." Vary the size of the target and repeat the experiment. Study the relationship between the area of the target and the...

Construct a box-and-whisker plot to match a line plots, and construct a line plot to match a box-and-whisker plots. Manipulate the line plot and examine how the box-and-whisker plot...

Add and subtract integers on a number line using dynamic arrows.

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Find the value of individual terms in an arithmetic or geometric sequence using graphs of the sequence and direct computation. Vary the common difference and common ratio and examine how...

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Conduct a phone poll of citizens in a small neighborhood to determine their response to a yes-or-no question. Use the results to estimate the sentiment of the entire population. Investigate...

Compare sample distributions drawn from population distributions. Predict characteristics of a population distribution based on a sample distribution and examine how well a small sample...

Extend understanding of fractions by making modern paintings in the style of Piet Mondrian. Create and analyze paintings with different-sized sections. Compare the sizes of unit fractions....

Model and compare fractions, decimals, and percents using area models. Each area model can have 10 or 100 sections and can be set to display a fraction, decimal, or percent. Click inside...

Construct models of gardens on a grid using squares of sod. Fence the gardens to find and compare perimeters. Work with pre-built gardens made of 36 squares each to compare perimeters of...

Use groups of critters on leaves to model multiplication as repeated addition. Change the expression to change the number of groups or the number of critters per group. Display the...

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Step right up! Spin the big wheel! Each spin can result in no prize, a small prize, or a big prize. The wheel can be spun by 1, 10, or 100 players. Results are recorded on a frequency table...

Participate in an old-fashioned quilting bee and create a colorful, symmetrical quilt. Quilts can be created with a vertical, horizontal, or diagonal line of symmetry. Quilts can be folded...

Operate an elevator in an old apartment building. Pick up and drop off residents where they want to go. A line graph shows where the elevator traveled over time. Operate the elevator either...

Go sightseeing in fictional cities all over the world. Learn about coordinates on a graph by navigating around these cities on a grid-like city map. Some landmarks are shown on the map. For...

Live a frog's life as you hop along a number line in search of flies. Learn how addition and subtraction can be represented as movement along a number line. Fred the frog may even help you...

Use base-10 blocks to model two numbers. Then combine the blocks to model the sum. Blocks of equal value can be exchanged from one area of the mat to the other to help understand carrying...

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Launch clowns from a circus cannon and try to hit the target. Drag digit cards on the control panel to set the launch distance and choose an appropriate unit of distance. After practicing...

Plan a cross-country road trip through various U.S. state capitals. First choose a vehicle to drive, and then fill up the tank with gas and go! Find the range and gas mileage of each...

Use base-10 blocks to model, add, and subtract whole numbers. Learn about place value using flats (hundreds), rods (tens), and cubes (ones). Group or ungroup blocks as needed to add or...

As factory belt operator, your job is to move boxes just the right distance on the belt, so they can be stamped for delivery. Your only controls are the radius and rotation of the belt’s...

Add real numbers using dynamic arrows on a number line. Find the sum of the numbers at the end of the final arrow. Compare the numerical calculation.

Find the value of individual terms in arithmetic sequences using graphs of the sequences and direct computation. Vary the common difference and examine how the sequences change in response.

Compare the graph of the sine function with the graph of the angle on the unit circle. Drag a point along the sine curve and see the corresponding angle on the unit circle.

Poll residents in a large city to determine their response to a yes-or-no question. Estimate the actual percentage of yes votes in the whole city. Examine the results of many polls to help...

Plant flowers in two gardens to help develop fraction sense. The two gardens act as number lines, from 0 to 1. Use the flowers in the gardens to compare fractions and to explore equivalent...

Use the Chocomatic to design candy bars made out of chocolate squares. Use multiplication to find the number of squares in each chocolate bar. Build collections of chocolate bars that all...

Movie reviewers rate movies on a scale of 0 to 10. Each movie comes with a set of reviews that can be changed by the user. The mean of a data set can be explored using a see-saw balance...

Test your reaction time by catching a falling ruler or clicking a target. Create a data set of experiment results, and calculate the range, mode, median, and mean of your data. Data can be...

Create your own rock art with ancient symbols. Each symbol can be translated, rotated, and reflected. After exploring each type of transformation, see if you can use them to match ancient...

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Drop a number into a function machine, and see what number comes out! You can use one of the six pre-set function machines, or program your own function rule into one of the blank machines....

Pick a duck, win a prize! Help Arnie the carnie design his game so that he makes money (or at least breaks even). How many ducks of each type should there be? What are the prizes worth? How...

Compare the graph of the cosine function with the graph of the angle on the unit circle. Drag a point along the cosine curve and see the corresponding angle on the unit circle.

Explore geometric sequences by varying the initial term and the common ratio and examining the graph. Compute specific terms in the sequence using the explicit and recursive formulas.

Compare the theoretical and experimental probabilities of drawing colored marbles from a bag. Record results of successive draws to find the experimental probability. Perform the drawings...

Use chips to model addition and subtraction of positives and negatives. Explore the effect of zero pairs. See how to use zero pairs to help special cases of addition and subtraction.

Create a graph (bar graph, line graph, pie chart, or scatter plot) based on a given data set. Title the graph, label the axes, and choose a scale. Adjust the graph to fit the data, and then...

Measure the height, diameter, and circumference of trees in a forest. Count growth rings to determine the age of each tree. Grow the trees for several years and investigate how growth is...

The alien school children from the planet Zigmo travel to distant planets on a field trip. The goal is to select a bus size so that all buses are full and no aliens are left behind. This...

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Create a set of stuffed animals: monkeys, giraffes, and rabbits. Toys can be painted red, green, or blue. Describe the makeup of the set (animals or colors) with fractions. Arrange the toys...

Model and compare decimals using area models. Set the number of sections in each model to 1, 10, or 100, and then click in the models to shade sections. Compare decimals visually and on a...

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Place points on a number line. Round these values to the nearest ten or hundred. Visualize rounding by showing the number line as a hill or series of hills. These hills cause the points to...

A brand new school is opening and it is time to elect the school mascot! Students can choose the Eagle, Lion, Bear, or Wolf. Voting results can be displayed in a table, tally chart,...

This Gizmo provides you with two challenges. First, use blocks to build a figure with a given volume. Then, try to balance the blocks on a platform that sits on the tip of a cone. The...

Explore the relationship between the correlation coefficient of a data set and its graph. Fit a line to the data and compare the least-squares fit line.

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Compare the graph of the tangent function with the graph of the angle on the unit circle. Drag a point along the tangent curve and see the corresponding angle on the unit circle.

Use grids to model decimal numbers and compare them graphically. Then compare the numbers on a number line.

Experiment with permutations and combinations of a number of letters represented by letter tiles selected at random from a box. Count the permutations and combinations using a dynamic tree...

A drug prescription must be carefully planned to maximize benefit while avoiding an overdose. In this Gizmo, you can give a patient one or more pills and monitor the levels of medication in...

Model and compare fractions using area models. Set the denominators with the arrow buttons, and then set the numerators with the arrow buttons or by clicking in the models. Compare...

Model numbers with base-10 blocks. Drag flats, rods, and individual cubes onto a mat to model a number. Blocks can be exchanged from one area of the mat to the other. Four sets of blocks...

Model the product of two decimals by finding the area of a rectangle. Estimate the area of the rectangle first. Then break the rectangle into several pieces and find the area of each piece...

Use base-10 blocks to model a starting number. Then subtract blocks from this number by dragging them into a subtraction bin. Blocks of equal value can be exchanged from one section of the...

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The Factor Trees Gizmo has two modes. In Factor mode, you can create factor trees to factor composite numbers into primes. In Build mode, you can build numbers by multiplying primes...

Drop a number into a function machine, and see what number comes out! You can use one of the six pre-set function machines, or program your own function rule into one of the blank machines....

Investigate the mean, median, mode, and range of a data set through its graph. Manipulate the data and watch how the mean, median, mode, and range change (or, in some cases, how they don't...

Experiment with spinners and compare the experimental probability of particular outcomes to the theoretical probability. Select the number of spinners, the number of sections on a spinner,...

Adjust the number of fish in a lake to be tagged and the number of fish to be recaptured. Use the number of tagged fish in the catch to estimate the number of fish in the lake.

When a foreign substance such as a drug is ingested, it often remains in the bloodstream for a long time. This Gizmo models the elimination of substances from the bloodstream using water...

Listen to and see interference patterns produced by sound waves with similar frequencies. Test your ability to distinguish and match sounds as musicians do when they tune their instruments....

Test your reaction time by catching a falling ruler or clicking a target. Create a data set of experiment results, and calculate the range, mode, median, and mean of your data. Data can be...

Add fractions with the help of the Fractionator, a fraction-tile-making machine in the Gizmo. Model sums by placing the tiles on side-by-side number lines. Explore the usefulness of common...

Drop a number into a function machine, and see what number comes out! You can use one of the six pre-set function machines, or program your own function rule into one of the blank machines....

Experiment with the graph of a sine or cosine function. Explore how changing the values in the equation can translate or scale the graph of the function.

Compare and order integers using draggable points on a number line. Also explore opposites and absolute values on the number line.

Experiment with spinners and compare the experimental probability of a particular outcome to the theoretical probability. Select the number of spinners, the number of sections on a spinner,...

Explore fractions using the Fractionator, the machine that makes fraction tiles. Compare fractions and find equivalent fractions by arranging the tiles on two horizontal rows. Explore...

Explore fractions greater than one with the Fractionator, a fraction-tile-making machine in the Gizmo. Create sums of fraction tiles on two number lines. Sums greater than one are shown as...

Fit a line to the data in a scatter plot using your own judgment. Then compare the least squares line of best fit.

Choose the correct steps to simplify a trigonometric function. Use step-by-step feedback to diagnose incorrect steps.

Change the values in a data set and examine how the dynamic histogram changes in response. Adjust the interval size of the histogram and see how the shape of the histogram is affected.

Drive a desert highway searching for buried treasure. Learn to use the car's tens, ones, tenths, and hundredths gears, along with a GPS system (number line), to find the right place to dig....

Play an addition card game! The goal is to create a sum that is as close as possible to the target sum. Students will deepen their understanding of place value as they get better at playing...

Choose the correct steps to evaluate a trigonometric expression using sum and difference identities. Use step-by-step feedback to diagnose incorrect steps.

Multiply two decimals using a dynamic area model. On a grid, shade the region with width equal to one of the decimals and height equal to the other decimal and find the area of the region.

You are the captain of an interplanetary cargo ship, delivering important supplies to the outer planets. The cargo can be stored in barrels, crates, and holds. (There are 10 barrels in a...

Develop understanding of fractions by making modern paintings. Find different ways to divide a canvas into equal-sized sections. Make paintings to represent simple fractions and to find...

Compare the graph of a circle with its equation. Vary the terms in the equation and explore how the circle is translated and scaled in response.

Order square roots on a number line. Approximate the square roots using the side lengths of square regions in a grid.

Examine the scatter plot for a random data set with negative or positive correlation. Vary the correlation and explore how correlation is reflected in the scatter plot and the trend line.

Solve an equation involving decimals using dynamic arrows on a number line.

Grumpy’s Restaurant is now hiring! As a new chef at this underwater bistro, you’ll learn the basics of manipulating algebraic expressions. Learn how to make equivalent expressions using the...

A farmer in Africa is having problems with elephants eating her corn and cotton crops. As a wildlife biologist, students learn about animal group behavior and relationships of elephants and...

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Explore the meaning of square roots using an area model. Use the side length of a square to find the square root of a decimal number or a whole number.

Examine the scatter plots for data related to weather at different latitudes. The Gizmo includes three different data sets, one with negative correlation, one positive, and one with no...

Find the sum or difference of two decimal numbers using area models. Find the decimals and their sum or difference on a number line.

Build a data set and find the mean, median, and mode. Explore the mean, median, and mode illustrated as frogs on a seesaw, frogs on a scale, and as frogs stacked under a bar of variable...

Drag blocks onto a two-dimensional surface and observe the effects on the center of mass. Use a grid to calculate the coordinates of the center of mass. Investigate predefined shapes or...

Build a data set and compare the line plot of the data set to the stem-and-leaf plot.

Resize a circle and compare its radius, circumference, and area.

Continue your meteoric rise in the undersea culinary world in this follow-up to Equivalent Algebraic Expressions I. Make equivalent expressions by using the distributive property forwards...

Meet Spidro, a quirky critter with an appetite for algebraic expressions! As Spidro's adopted owner, it's your responsibility to feed him so that he grows into… whatever it is that a Spidro...

Will you adopt Spidro, Centeon, or Ping Bee? They're three very different critters with one thing in common: a hunger for simplified algebraic expressions! Learn how the distributive...

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Are there times when you wish you could escape from everyone and just be alone? Meet our variable friend, a real loner who doesn't like coefficients and neighboring terms. Learn how to use...

Is solving equations tricky? If you know how to isolate a variable, you're halfway there. The other half? Don't do anything to upset the balance of an equation. Join our plucky variable...

Solve inequalities in one variable. Examine the inequality on a number line and determine which points are solutions to the inequality.

Explore the relationship between a central angle and the arcs it intercepts. Also explore the relationship between chords and their distance from the circle's center.

Solve a two-step equation using a cup-and-counter model. Use step-by-step feedback to diagnose and correct incorrect steps.

Solve a linear equation using a tile model. Use feedback to diagnose incorrect steps.

Resize angles inscribed in a circle. Investigate the relationship between inscribed angles and the arcs they intercept.

Select and evaluate the operations in an expression following the correct order of operations.

Solve an equation by graphing each side and finding the intersection of the lines. Vary the coefficients in the equation and explore how the graph changes in response.

Translate algebraic expressions into English phrases, and translate English phrases into algebraic expressions. Read the expression or phrase and select word tiles or symbol tiles to form...

Translate equations into English sentences and translate English sentences into equations. Read the equation or sentence and select word tiles or symbol tiles to form the corresponding...

Choose the correct steps to solve a formula for a given variable. Use the feedback to diagnose incorrect steps.

Solve one-step inequalities in one variable. Graph the solution on a number line.

Choose the correct steps to solve a two-step equation. Use the feedback to diagnose incorrect steps.

Use a number line to compare rational numbers. Change values by dragging points on the number line. Compare the opposites and absolute values of the numbers.

Divide fractions using area models. Adjust the numerators and denominators of the divisor and dividend and see how the area model and calculation change.

Choose the correct steps to divide mixed numbers. Use step-by-step feedback to diagnose and correct incorrect steps.

Estimate the sum or difference of two fractions using area models. Compare estimates to exact sums and differences.

Find factors of a number using an area model. Reshape the area rectangle to see different factorizations of the number. Find the prime factorization using a factor tree.

Find the sum or difference of two fractions with unlike denominators using graphic models. Find the least common denominator graphically.

Choose the correct steps to multiply mixed numbers. Use the step-by-step feedback to diagnose incorrect steps.

Compare a quantity represented by an area with its percent, fraction, and decimal forms.

Represent a quantity given by a shaded region as an improper fraction and as a mixed number. Experiment with different shaded regions sliced differently.

Compare and order numbers greater than 1 using area grids and a number line. Examine the numbers represented as percents, improper fractions, and decimals.

Multiply two fractions using an area model. Vary the vertical area to change one fraction and vary the horizontal area to change the other. Then examine the intersection of the areas to...

A farmer in Africa is having problems with elephants eating her corn and cotton crops. As a wildlife biologist, students learn about animal group behavior and relationships of elephants and...

Apply ratios and proportions to find the weight of a person on the moon (or on another planet). Weigh an object on Earth and on the moon and weigh the person on Earth. Then set up and solve...

Compare a ratio represented by an area with its percent, fraction, and decimal forms.

Apply markups and discounts using interactive "percent rulers." Improve number sense for percents with this dynamic, visual tool. Reinforce the original cost (or original price) as the...

Find a part from the percent and whole, a percent from the part and whole, or a whole from the part and percent using a graphic model.

Complete a proportion using a graphical model. Use counters to fill cells in the numerators and denominators given. Use the visual pattern to determine how many counters to put in the...

Create a graph of a runner's position versus time and watch the runner run a 40-yard dash based on the graph you made. Notice the connection between the slope of the line and the velocity...

Create a graph of a runner's position versus time and watch the runner run a 40-meter dash based on the graph you made. Notice the connection between the slope of the line and the velocity...

Apply ratios and proportions to find the weight of a person on the moon (or on another planet). Weigh an object on Earth and on the moon and weigh the person on Earth. Then set up and solve...

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Explore number systems and convert numbers from one base to another using counter beads in place-value columns.

Choose the correct steps to simplify expressions with exponents using the rules of exponents and powers. Use feedback to diagnose incorrect steps.

Choose the correct steps to divide exponential expressions. Use the feedback to diagnose incorrect steps.

Choose the correct steps to multiply exponential expressions. Use the feedback to diagnose incorrect steps.

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Build a pattern to complete a sequence of patterns. Study a sequence of three patterns of squares in a grid and build the fourth pattern of the sequence in a grid.

Determine if a relation is a function using the mapping diagram, ordered pairs, or the graph of the relation. Drag arrows from the domain to the range, type in ordered pairs, or drag points...

Determine if a relation is a function from the mapping diagram, ordered pairs, or graph. Use the graph to determine if it is linear.

Compare the graph of a linear function to its rule and to a table of its values. Change the function by dragging two points on the line. Examine how the rule and table change.

Explore the slope of a line, and learn how to calculate slope. Adjust the line by moving points that are on the line, and see how its slope changes.

Identify the coordinates of a point in the coordinate plane. Drag the point in the plane and investigate how the coordinates change in response.

Compare the standard form of a linear equation to its graph. Vary the coefficients and explore how the graph changes in response.

Compare the point-slope form of a linear equation to its graph. Vary the coefficients and explore how the graph changes in response.

Compare the slope-intercept form of a linear equation to its graph. Vary the coefficients and explore how the graph changes in response.

Experiment with a system of two lines representing a cat-and-mouse chase. Adjust the speeds of the cat and mouse and the head start of the mouse, and immediately see the effects on the...

Solve systems of linear equations, given in slope-intercept form, both graphically and algebraically. Use a draggable green point to examine what it means for an (x, y) point to be a...

Adjust the constant of variation and explore how the graph of the direct or inverse variation function changes in response. Compare direct variation functions to inverse variation...

Find the solution set to a linear inequality in two variables using the graph of the linear inequality. Vary the terms of the inequality and vary the inequality symbol. Examine how the...

Create a graph of a runner's position versus time and watch the runner complete a 40-yard dash based on the graph you made. Notice the connection between the slope of the line and the speed...

Explore compound interest in-depth, from compounded annually to compounded continuously. In addition, compare the END POINTS graph, with dots that fit an exponential curve, to the ALL TIME...

Experiment with a system of two lines representing a cat-and-mouse chase. Adjust the speeds of the cat and mouse and the head start of the mouse, and immediately see the effects on the...

Create a graph of a runner's position versus time and watch the runner complete a 40-meter dash based on the graph you made. Notice the connection between the slope of the line and the...

Add polynomials using an area model. Use step-by-step feedback to diagnose any mistakes.

Explore the graph of an exponential function. Vary the coefficient and base of the function and investigate the changes to the graph of the function.

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Create a polynomial as a product of linear factors. Vary the values in the linear factors to see how their connection to the roots of the function.

Explore the relationships between perpendicular bisectors, the circumscribed circle, angle bisectors, the inscribed circle, altitudes, and medians using a triangle that can be resized and...

Construct parallel and perpendicular lines using a straightedge and compass. Use step-by-step explanations and feedback to develop understanding of the construction.

Construct congruent segments and angles using a straightedge and compass. Use step-by-step explanations and feedback to develop understanding of the construction.

Explore the properties of complementary, supplementary, vertical, and adjacent angles using a dynamic figure.

Explore the properties of intersecting, parallel, and skew lines as well as lines in the plane. Rotate the plane and lines in three-dimensional space to ensure a full understanding of...

Use a dynamic triangle to explore the area of a triangle. With the help of an animation, see that any triangle is always half of a parallelogram (with the same base and height). Likewise, a...

Apply constraints to a quadrilateral, and then reshape and resize it. Classify the figure by its constraints. Explore the differences between the different kinds of quadrilaterals.

Apply constraints to a dynamic quadrilateral. Then drag its vertices around. Determine which constraints guarantee that the quadrilateral is always a parallelogram.

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Derive the sum of the angles of a polygon by dividing the polygon into triangles and summing their angles. Vary the number of sides and determine how the sum of the angles changes. Dilate...

Apply constraints to a parallelogram and experiment with the resulting figure. What type of shape can you be sure that you have under each condition?

Examine and manipulate a parallelogram and find its area. Explore the relationship between the area of a parallelogram and the area of a rectangle using an animation.

Explore the special properties of a point that lies on the perpendicular bisector of a segment, and of a point that lies on an angle bisector. Manipulate the point, the segment, and the...

Apply constraints to two right triangles. Then drag their vertices around under those conditions. Determine under what conditions the triangles are guaranteed to be congruent.

Investigate the graph of a triangle under constraints. Determine which constraints guarantee isosceles or equilateral triangles.

Apply constraints to two triangles. Then drag the vertices of the triangles around and determine which constraints guarantee congruence.

Divide a right triangle at the altitude to the hypotenuse to get two similar right triangles. Explore the relationship between the two triangles.

Measure the interior angles of a triangle and find the sum. Examine whether that sum is the same for all triangles. Also, discover how the measure of an exterior angle relates to the...

Discover the inequalities related to the side lengths and angle measures of a triangle. Reshape and resize the triangle to confirm that these properties are true for all triangles.

Place constraints on a triangle and determine what classifications must apply to the triangle.

Explore the distance formula as an application of the Pythagorean theorem. Learn to see any two points as the endpoints of the hypotenuse of a right triangle. Drag those points and...

Explore the Pythagorean Theorem using a dynamic right triangle. Examine a visual, geometric application of the Pythagorean Theorem, using the areas of squares on the sides of the triangle.

Build right triangles in an interactive geoboard and build squares on the sides of the triangles to discover the Pythagorean Theorem.

Reshape and resize a right triangle and examine how the sine of angle A, the cosine of angle A, and the tangent of angle A change.

Vary the coefficients in the equation of a function and examine how the graph of the function is translated or scaled. Select different functions to translate and scale, and determine what...

Dilate a figure and investigate its resized image. See how scaling a figure affects the coordinates of its vertices, both in (x, y) form and in matrix form.

Manipulate two similar figures and vary the scale factor to see what changes are possible under similarity. Explore how the perimeters and areas of two similar figures compare.

Reshape and resize a figure and examine how its reflection changes in response. Move the line of reflection and explore how the reflection is translated.

Translate a figure horizontally and vertically in the plane and examine the matrix representation of the translation.

Rotate, reflect, and translate a figure in the plane. Compare the translated figure to the original figure.

Vary the scale factor and rotation of an image and compare it to the preimage. Determine how the angle measures and side lengths of the two figures are related.

Arrange blocks in a three-dimensional space so that the top view, front view, and side view match the target top view, front view, and side view.

Vary the height and base-edge or radius length of a pyramid or cone and examine how its three-dimensional representation changes. Determine the area of the base and the volume of the...

Vary the height and base-edge or radius length of a prism or cylinder and examine how its three-dimensional representation changes. Determine the area of the base and the volume of the...

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Vary the dimensions of a prism or cylinder and investigate how the surface area changes. Use the dynamic net of the solid to compute the lateral area and the surface area of the solid.

Vary the dimensions of a pyramid or cone and investigate how the surface area changes. Use the dynamic net of the solid to compute the lateral area and the surface area of the solid.

Discover how to find the perimeter and area of a rectangle, and of a square (which is really just a special case of a rectangle).

Calculate the difference between the times given by two analog clocks. Rotate the hands of the clocks to change the time and see how the calculation changes.

Identify the imaginary and real coordinates of a point in the complex plane. Drag the point in the plane and investigate how the coordinates change in response.

Find the root of a quadratic using its graph or the quadratic formula. Explore the graph of the roots and the point of symmetry in the complex plane. Compare the axis of symmetry and...

Explore systems of linear equations, and how many solutions a system can have. Express systems in matrix form. See how the determinant of the coefficient matrix reveals how many solutions a...

Explore the graphs of two inequalities and find their union or intersection. Determine the relationship between the endpoints of the inequalities and the endpoints of the compound...

Solve an inequality involving absolute values using a graph of the absolute-value function. Vary the terms of the absolute-value function and vary the value that you are comparing it to. ...

Solve systems of linear equations, written in standard form. Explore what it means to solve systems algebraically (with substitution or elimination) and graphically. Also, use a draggable...

Use the graph of the feasible region to find the maximum or minimum value of the objective function. Vary the coefficients of the objective function and vary the constraints. Explore how...

Compare a system of linear inequalities to its graph. Vary the coefficients and inequality symbols in the system and explore how the boundary lines, shaded regions, and the intersection of...

Adjust the values in a quadratic function, in vertex form or in polynomial form, to "zap" as many data points as possible.

Investigate the factors of a quadratic through its graph and through its equation. Vary the roots of the quadratic and examine how the graph and the equation change in response.

Compare the graph of a quadratic to its equation in polynomial form. Vary the coefficients of the equation and explore how the graph changes in response.

Find the solution set to a quadratic inequality using its graph. Vary the terms of the inequality and the inequality symbol. Examine how the boundary curve and shaded region change in...

Compare the graph of a quadratic to its equation in vertex form. Vary the terms of the equation and explore how the graph changes in response.

Compare the graph of a linear function, the graph of an absolute-value function, and the graphs of their translations. Vary the coefficients and constants in the functions and investigate...

Identify the correct steps to complete operations with a radical expression. Use step-by-step feedback to diagnose incorrect steps.

Simplify a radical expression. Use step-by-step feedback to diagnose any incorrect steps.

Compare the graph of a radical function to its equation. Vary the terms of the equation. Explore how the graph is translated and stretched by the changes to the equation.

Vary the values in the equation of a logarithmic function and examine how the graph is translated or scaled. Connect these transformations with the domain of the function, and the...

Explore the graph of the exponential growth or decay function. Vary the initial amount and the rate of growth or decay and investigate the changes to the graph.

Explore the graph of the exponential function. Vary the initial amount and base of the function. Investigate the changes to the graph.

Compare the equation of a logarithmic function to its graph. Change the base of the logarithmic function and examine how the graph changes in response. Use the line y = x to compare the...

Compare the equation of a rational function to its graph. Multiply or divide the numerator and denominator by linear factors and explore how the graph changes in response.

Compare the graph of a rational function to its equation. Vary the terms of the equation and explore how the graph is translated and stretched as a result. Examine the domain on a number...

Explore the graphs of two polynomials and the graph of their sum or difference. Vary the coefficients in the polynomials and investigate how the graphs change in response.

Choose the correct steps to factor a polynomial involving perfect-square binomials, differences of squares, or constant factors. Use the feedback to diagnose incorrect steps.

Factor a polynomial with a leading coefficient greater than 1 using an area model. Use step-by-step feedback to diagnose any mistakes.

Factor a polynomial with a leading coefficient equal to 1 using an area model. Use step-by-step feedback to diagnose any mistakes.

Divide a polynomial by dragging the correct numbers into the correct positions for synthetic division. Compare the interpreted polynomial division to the synthetic division.

Study the graphs of polynomials up to the fourth degree. Vary the coefficients of the equation and investigate how the graph changes in response. Explore things like intercepts, end...

Compare the equation of an ellipse to its graph. Vary the terms of the equation of the ellipse and examine how the graph changes in response. Drag the vertices and foci, explore their...

Compare the equation of a hyperbola to its graph. Vary the terms of the equation of the hyperbola. Examine how the graph of the hyperbola and its asymptotes changes in response.

Explore parabolas in a conic section context. Find the relationship among the vertex, focus, and directrix of a parabola, and how that relates to its equation.

Make a biconditional statement from a given definition using word tiles. Use both symbolic form and standard English form.

Make a conditional statement from a given fact using word tiles. Use both symbolic form and standard English form.

Approximate the area under a curve in an interval using rectangles. Compare the results of left-hand summation to the results of right-hand summation. Vary the interval and the number of...

Move, rotate, and resize two vectors in a plane. Find their resultant, both graphically and by direct computation.

Explore a wide variety of cells, from bacteria to human neurons, using a compound light microscope. Select a sample to study, then focus on the sample using the coarse and fine focus...

Use a scalpel, forceps, and pins to dissect realistic male and female frogs. Organs can be removed and placed into organ system diagrams. Once the dissections are complete, the frog organ...

Create a graph of a runner's position versus time and watch the runner complete a 40-yard dash based on the graph you made. Notice the connection between the slope of the line and the speed...

Adjust the number of fish in a lake to be tagged and the number of fish to be recaptured. Use the number of tagged fish in the catch to estimate the number of fish in the lake.

Use a sonar on a boat to remotely measure the depth of an ocean at various locations. Describe multiple points on the ocean floor using their latitude, longitude, and depth. View maps of...

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Observe the spread of disease through a group of people. The methods of transmission can be chosen and include person-to-person, airborne, and foodborne as well as any combination thereof....

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In this ecosystem consisting of hawks, snakes, rabbits and grass, the population of each species can be studied as part of a food chain. Disease can be introduced for any species, and the...

Learn how to determine the mass of an object using a triple beam balance. The mass of a variety of objects can be determined using this simulated version of a common real-world laboratory...

Investigate the motion of an object as it falls to the ground. A variety of objects can be compared, and their motion can be observed in a vacuum, in normal air, and in denser air. The...

Practice measuring the period of a pendulum. Perform experiments to determine how mass, length, gravitational acceleration, and angle affect the period of a pendulum.

Study photosynthesis in a variety of conditions. Oxygen production is used to measure the rate of photosynthesis. Light intensity, carbon dioxide levels, temperature, and wavelength of...

Gain an understanding of Newton's Laws by experimenting with a cart (on which up to three fans are placed) on a linear track. The cart has a mass, as does each fan. The fans exert a...

Learn why the temperature in the summertime is higher than it is in the winter by studying the amount of light striking the Earth. Experiment with a plate detector to measure the amount of...

Point a laser at a mirror and compare the angle of the incoming beam to the angle of reflection. A protractor can be used to measure the angles of incidence and reflection, and the angle of...

Use protons, neutrons, and electrons to build elements. As the number of protons, neutrons, and electrons changes, information such as the name and symbol of the element, the Z, N, and A...

Measure the temperature on wet and dry bulb thermometers to determine relative humidity. Measure the dew point by cooling a bucket of water until condensation forms on the surface. See how...

Control the temperature of a beaker of water. As the temperature drops below the freezing point, a transformation of state will occur that can be viewed on a molecular level. Salt can be...

A collection of stars visible from Earth can be arranged and classified based on their color, temperature, luminosity, radius, and mass. This can be done using one or two-dimensional...

Control the path of a drop of water as it travels through the water cycle. Many alternatives are presented at each stage. Determine how the water moves from one location to another, and...

Try to classify a dozen different rock samples based on their appearance. Common characteristics of each major rock type are described. Rocks also can be classified by where they formed.

Survey the solar system, observing the length of a year and the orbital path of each object. The positions of the eight official planets are displayed, as well as one dwarf planet, Pluto....

Explore the energy used by many household appliances, such as television sets, hair dryers, lights, computers, etc. Make estimates for how long each item is used on a daily basis to get an...

Breed "pure" mice with known genotypes that exhibit specific fur colors, and learn how traits are passed on via dominant and recessive genes. Mice can be stored in cages for future...

Select a sample cell from an animal, plant, or bacterium and view the cell under a microscope. Select each organelle on the image to learn more about its structure and function. Closeup...

Observe the partial shadows cast by a rectangular block lit by multiple light sources. The number of light sources ranges from one to five, and individual lights can be turned on or off....

Understand how topographic maps work by creating a three-dimensional landscape and observing the corresponding contour lines. See how mountains, depressions, valleys and cliffs are...

Simulate ionic bonds between a variety of metals and nonmetals. Select a metal and a nonmetal atom, and transfer electrons from one to the other. Observe the effect of gaining and losing...

Test your hearing range by listening to low-, medium-, and high-frequency sounds. Compare the relative loudness of sounds at each frequency to create an equal-loudness curve. In a quiet...

Explore the relationship between molecular motion, temperature, and phase changes. Compare the molecular structure of solids, liquids, and gases. Graph temperature changes as ice is melted...

Understand the phases of the Moon by observing the positions of the Moon, Earth and Sun. A view of the Moon from Earth is shown on the right as the Moon orbits Earth. Learn the names of...

Investigate the growth of three common garden plants: tomatoes, beans, and turnips. You can change the amount of light each plant gets, the amount of water added each day, and the type of...

Launch a charged particle into a chamber. Charged particles can be added into the chamber to influence the path of the moving particle. The launch speed can be changed as well. Try to match...

Explore our solar system and learn the characteristics of each planet. Compare the sizes of planets and their distances from the Sun. Observe the speeds of planetary orbits and measure how...

Observe and measure the properties of a mineral sample, and then use a key to identify the mineral. Students can observe the color, luster, shape, density, hardness, streak, and reaction to...

Find the effect of length, mass, and angle on the period of a pendulum. The pendulum is attached to a clock that can be adjusted to tell time accurately. The clock can be located on Earth...

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Use a lever to lift a pig, turkey, or sheep. A strongman provides up to 1000 newtons of effort. The fulcrum, strongman, and animals can be moved to any position to create first-, second-,...

Observe the populations of grass, prairie dogs, ferrets and foxes in a prairie ecosystem. Investigate feeding relationships and determine the food chain. Bar graphs and line graphs show...

Lift food using ants with the help of a slanted stick. The steepness of the stick, the number of ants, and the size of the item being lifted can be varied. Observe the effect of friction on...

Recreate Galileo's famous experiment by dropping objects off the Tower of Pisa. You can drop ping pong balls, golf balls, soccer balls or watermelons. Objects can be dropped in air or no...

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Where does energy come from? How does energy get from one place to another? Find out how electrical current is generated and how living things get energy to move and grow. Trace the path of...

Shine a powerful flashlight on a variety of materials, and measure how quickly each material heats up. See how the light angle, light color, type of material, and material color affect...

Create aliens with different traits and breed them to produce offspring. Determine which traits are passed down from parents to offspring and which traits are acquired. Offspring can be...

Go on an African safari and observe a variety of animals walking and running across the savanna. Videotape the animals, and then play back the videotape to estimate animal speeds. Which...

Heat or cool a container of water and observe the phase changes that take place. Use a magnifying glass to observe water molecules as a solid, liquid, or gas. Compare the volumes of the...

Trace the path of blood through a beating heart and the network of blood vessels that supplies blood to the body. Take blood samples from different blood vessels to observe blood cells and...

Measure the height, diameter, and circumference of trees in a forest. Count growth rings to determine the age of each tree. Grow the trees for several years and investigate how growth is...

Observe and measure transverse, longitudinal, and combined waves on a model of a spring moved by a hand. Adjust the amplitude and frequency of the hand, and the tension and density of the...

Explore acceleration, speed, momentum, and energy by sending a sled down a hill into a group of snowmen. The starting height and mass of the sled can be changed, as well as the number of...

Chemical changes result in the formation of new substances. But how can you tell if a chemical change has occurred? Explore this question by observing and measuring a variety of chemical...

How do scientists measure and describe the weather? In this introductory lesson, students will practice using a thermometer, anemometer, rain gauge, and hygrometer to record weather...

Everything we know about the world comes through our senses: sight, hearing, touch, taste, and smell. In the Senses Gizmo, explore how stimuli are detected by specialized cells, transmitted...

Design a car to protect a test dummy in a collision. Adjust the length and stiffness of the crumple zone and the rigidity of the safety cell to determine how the car will deform during the...

Explore life in the hive by meeting workers, drones, and the queen bee herself! Visit flower patches to determine the best sources of food, and then perform a waggle dance to let the other...

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In this introduction to coding, program a rover to explore the surface of Mars. Start by using tiles to create simple programs involving moving forward or backward, turns, jumps, loops, and...

Collect fingerprints from simulated crime scenes using a camera, fingerprinting powder, and tape. Classify fingerprints into groups and subgroups, then identify minutiae. Match collected...

Design a house to withstand an earthquake and protect the people living inside. Select a location in San Francisco, then choose the design and materials for a foundation, frame, walls, and...

Working as a CDC researcher, students investigate an outbreak of multi-drug resistant bacterial infections and determine how evolution was involved by tracing the source and cause of the...

As a veterinary technician, students learn about enzymes to help a dog that has been eating normally but is losing a lot of weight.

Observe the motions of Venus and Earth as the planets move around the Sun. Measure the length of a day and a year on Earth and Venus, and compare the length of a solar day to the length of...

Observe the population of rabbits in an environment over many years. The land available to the rabbits and weather conditions can be adjusted to investigate the effects of urban sprawl and...

Breed "pure" mice with known genotypes that exhibit specific fur and eye colors, and learn how traits are passed on via dominant and recessive genes. Mice can be stored in cages for future...

Compare the potential energy of several objects when you place them on shelves of different heights. Learn that two objects at different heights can have the same potential energy, while...

Adjust the hills on a toy-car roller coaster and watch what happens as the car careens toward an egg (that can be broken) at the end of the track. The heights of three hills can be...

Balance and classify five types of chemical reactions: synthesis, decomposition, single replacement, double replacement, and combustion. While balancing the reactions, the number of atoms...

Measure the period of a mass on the end of a spring. Determine the effects of gravitational acceleration, mass, and the spring constant on the period of the spring. Create an equation for...

Begin with a single cell and watch as mitosis and cell division occurs. The cells will go through the steps of interphase, prophase, metaphase, anaphase, telophase, and cytokinesis. The...

You are a bird hunting moths (both dark and light) that live on trees. As you capture the moths most easily visible against the tree surface, the moth populations change, illustrating the...

Use a variety of real-world lab tests to analyze common food samples in order to determine if the food is a carbohydrate, a protein, or a lipid. Tests that can be performed include:...

Explore the processes of photosynthesis and respiration that occur within plant and animal cells. The cyclical nature of the two processes can be constructed visually, and the simplified...

Gain an understanding of moonrise and moonset times by observing the relative positions of Earth and the Moon along with a view of the Moon from Earth. A line shows the horizon for a person...

Observe the motions of the Earth, Moon and Sun in three dimensions to explain Sunrise and Sunset, and to see how we define a day, a month, and a year. Compare times of Sunrise and Sunset...

Build a topographic map by flooding a three dimensional landscape with water and drawing contour lines. Draw a profile of a landscape based on the topographic map.

Determine how the physical properties of a solvent are dependent on the number of solute particles present. Measure the vapor pressure, boiling point, freezing point, and osmotic pressure...

Choose a substance, and then move electrons between atoms to form covalent bonds and build molecules. Observe the orbits of shared electrons in single, double, and triple covalent bonds....

When a foreign substance such as a drug is ingested, it often remains in the bloodstream for a long time. This Gizmo models the elimination of substances from the bloodstream using water...

Listen to and see interference patterns produced by sound waves with similar frequencies. Test your ability to distinguish and match sounds as musicians do when they tune their instruments....

Determine the angle of refraction for a light beam moving from one medium to another. The angle of incidence and each index of refraction can be varied. Using the tools provided, the angle...

Analyze the spectra of a variety of stars. Determine the elements that are represented in each spectrum, and use this information to infer the temperature and classification of the star....

Use a pulley system to lift a heavy weight to a certain height. Measure the force required to lift the weight using up to three fixed and three movable pulleys. The weight to be lifted and...

Shine white light or a single-color beam through a prism. Explore how a prism refracts light and investigate the factors that affect the amount of refraction. The index of refraction of the...

Create a graph of a runner's position versus time and watch the runner complete a 40-meter dash based on the graph you made. Notice the connection between the slope of the line and the...

Observe daily weather conditions in a coastal region. Measure temperatures and wind speeds at any location and use this data to map convection currents that form during the day and night....

Drag bar magnets and a variety of other objects onto a piece of paper. Click Play to release the objects to see if they are attracted together, repelled apart, or unaffected. You can also...

Develop an understanding of ocean tides by comparing the depth of water near a dock to the positions of the Moon, Sun, and Earth. Determine the influence of the Moon and Sun on tides, and...

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Plant seeds and watch how many sprout. Examine what factors affect germination. Vary the amount of heat, water, and light the seeds get. Practice designing controlled experiments and using...

Create circuits using batteries, light bulbs, switches, fuses, and a variety of materials. Examine series and parallel circuits, conductors and insulators, and the effects of battery...

Observe and manipulate the populations of four creatures (trees, deer, bears, and mushrooms) in a forest. Investigate the feeding relationships (food web) in the forest. Determine which...

Observe solar and lunar eclipses as the Moon orbits Earth. The full and partial shadows of the Moon and Earth can be displayed, and the Moon can also be dragged around Earth. See what the...

Imagine a gigantic pitcher standing on Earth, ready to hurl a huge baseball. What will happen as the ball is thrown harder and harder? Find out with the Gravity Pitch Gizmo. Observe the...

Use a balance to measure mass and a spring scale to measure the weight of objects. Compare the masses and weights of objects on Earth, Mars, Jupiter, and the Moon.

Observe frogs jumping around on colored lily pads. Find, test, and reason about patterns you see in their jumping.

Measure the temperature and oxygen content of a pond over the course of a day. Then go fishing to see what types of fish live in the pond. Many different ponds can be investigated to...

Use a powerful flashlight to pop a kernel of popcorn. A lens focuses light on the kernel. The temperature of the filament and the distance between the flashlight and lens can be changed....

Study wave motion, diffraction, interference, and refraction in a simulated ripple tank. A wide variety of scenarios can be chosen, including barriers with one or two gaps, multiple wave...

Measure the volume of liquids and solids using beakers, graduated cylinders, overflow cups, and rulers. Water can be poured from one container to another and objects can be added to...

Digestion is a complex process, involving a wide variety of organs and chemicals that work together to break down food, absorb nutrients, and eliminate wastes. But have you ever wondered...

Design your own trebuchet to fling a projectile at a castle wall. All of the dimensions of the trebuchet can be adjusted, as well as the masses of the counterweight and payload. Select a...

How do scientists measure and describe the weather? In this introductory lesson, students will practice using a thermometer, anemometer, rain gauge, and hygrometer to record weather...

Use genetic engineering techniques to create corn plants resistant to insect pests or tolerant of herbicides. Identify useful genes from bacteria, insert the desired gene into a corn plant,...

Explore what isotopes are by adding protons and neutrons to the nucleus of an atom. Plot both stable and radioactive isotopes on a graph of neutrons vs. protons, and explore how the...

Learn how DNA is compared to identify individuals. Identify the sections of DNA that tend to differ and use PCR to amplify these segments. Then use gel electrophoresis to create DNA...

Observe how different colors of light are reflected or absorbed by colored objects. Determine that white light is a combination of different colors of light, and that one or more component...

Create molecules using building blocks of carbon, hydrogen, oxygen, nitrogen, and other elements. Connect atoms by bonds, then create double or triple bonds if desired. For each completed...

Build a home to survive a flood or a hurricane and protect the people inside. Choose materials and a design for the foundation, frame, walls, and roof of the house. Add "extras" such as...

The Secret Service recently arrested suspects accused of counterfeiting coins from 1915 valued at $50,000 each. The students act as a forensic scientist to investigate the crime scene and...

Measure your reaction time by clicking your mouse as quickly as possible when visual or auditory stimuli are presented. The individual response times are recorded, as well as the mean and...

Observe two different forms of simple harmonic motion: a pendulum and a spring supporting a mass. Use a stopwatch to measure the period of each device as you adjust the mass hanging from...

Create a graph of a runner's position versus time and watch the runner run a 40-yard dash based on the graph you made. Notice the connection between the slope of the line and the velocity...

With a scale to measure mass, a graduated cylinder to measure volume, and a large beaker of liquid to observe flotation, the relationship between mass, volume, density, and flotation can be...

Observe sound waves emitted from a moving vehicle. Measure the frequency of sound waves in front of and behind the vehicle as it moves, illustrating the Doppler effect. The frequency of...

Gain an understanding of high, low, spring, and neap tides on Earth by observing the tidal heights and the positions of the Earth, Moon, and Sun. Tidal bulges can be observed from space,...

Add varying amounts of a chemical to a beaker of water to create a solution, observe that the chemical dissolves in the water at first, and then measure the concentration of the solution at...

Shine sunlight through a prism and use a thermometer to measure the temperature in different regions of the spectrum. The thermometer can be dragged through the visible spectrum and beyond....

Using the scientific method, control the environmental conditions for a fictional alien organism in order to learn how the organism responds to changes in conditions. Sunlight, water, and...

Build electrical circuits using batteries, light bulbs, resistors, fuses, wires, and a switch. An ammeter, a voltmeter and an ohmmeter are available for measuring current, voltage and...

Drag two objects around and observe the gravitational force between them as their positions change. The mass of each object can be adjusted, and the gravitational force is displayed both as...

Perform multiple experiments using several common powders such as corn starch, baking powder, baking soda, salt, and gelatin. The results of the research on the known powders can then be...

Play the role of a piece of rock moving through the rock cycle. Select a starting location and follow many possible paths throughout the cycle. Learn how rocks are formed, weathered,...

Observe daily weather conditions in a coastal region. Measure temperatures and wind speeds at any location and use this data to map convection currents that form during the day and night....

Get to know the four main types of pollution present in the environment, and then look at a variety of real-world examples as you try to guess what type of pollution is represented by each...

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Breed "pure" chickens with known genotypes that exhibit specific feather colors, and learn how traits are passed on via codominant genes. Chickens can be stored in cages for future...

Practice balancing chemical equations by changing the coefficients of reactants and products. As the equation is manipulated, the amount of each element is shown as individual atoms,...

Gain an understanding of the causes of seasons by observing Earth as it orbits the Sun in three dimensions. Observe the path of the Sun across the sky on any date and from any location....

Build a glucose molecule, atom-by-atom, to learn about chemical bonds and the structure of glucose. Explore the processes of dehydration synthesis and hydrolysis in carbohydrate molecules.

Observe how a paramecium maintains stable internal conditions in a changing aquatic environment. Water moves into the organism by osmosis, and is pumped out by the contractile vacuole. The...

A drug prescription must be carefully planned to maximize benefit while avoiding an overdose. In this Gizmo, you can give a patient one or more pills and monitor the levels of medication in...

Observe evolution in a fictional population of bugs. Set the background to any color, and see natural selection taking place. Inheritance of color occurs according to Mendel's laws and...

Manipulate the position of the Moon to model solar and lunar eclipses. View Earth's shadow, the Moon's shadow, or both. Observe the Moon and Sun from Earth during a partial and total...

Place weights into a boat and see how far the boat sinks into a tank of liquid. The depth of the boat can be measured, as well as the amount of liquid displaced. The dimensions of the boat...

Observe the propagation of longitudinal (compression) waves in a closed or open tube with evenly-spaced dividers. The strength and frequency of the waves can be manipulated, or waves can be...

Explore the laws of motion using a simple fan cart. Use the buttons to select the speed of the fan and the surface, and press Play to begin. You can drag up to three objects onto the fan...

Observe the steps of pollination and fertilization in flowering plants. Help with many parts of the process by dragging pollen grains to the stigma, dragging sperm to the ovules, and...

Lift a variety of heavy objects (armchair, safe, piano) using pulleys and a rope. Systems of one, two, four, or six pulleys can be used. Up to six people can be used to pull on the rope,...

Use a wheel and axle to move a heavy load. Find out how many athletes it takes to move the load under different conditions. The radii of the wheel and the axle can be adjusted to help study...

Two flasks hold colored water, one yellow and the other blue. Set the starting temperature of each flask, choose a type of material to connect the flasks, and see how quickly the flasks...

Follow in the footsteps of Edwin Hubble to discover evidence supporting the Big Bang Theory. First, observe Cepheid variable stars in different galaxies to determine their distances. Then,...

Follow the path of a carbon atom through the atmosphere, biosphere, hydrosphere, and geosphere. Manipulate a simplified model to see how human activities and other factors affect the amount...

Compare average temperatures, precipitation, humidity, and wind speed for a variety of locations across the globe. Explore the influence of latitude, proximity to oceans, elevation, and...

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In this follow-up to the Genetic Engineering Gizmo, explore how farmers can maximize yield while limiting ecosystem damage using genetically modified corn. Choose the corn type to plant and...

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Grow Wisconsin Fast Plants® in a simulated lab environment. Explore the life cycles of these plants and how their growth is influenced by light, water, and crowding. Practice pollinating...

The atomic mass for each element listed in the periodic table is actually the weighted average mass of all of the different isotopes of the element. In the Average Atomic Mass Gizmo, use a...

Once light enters the eye, it must be focused on the retina. Manipulate the pupil diameter to regulate the amount of light that enters then eye, then change the lens shape to focus light....

As a marine biologist students learn about photosynthesis to help scientists in Australia determine why the coral in the Great Barrier Reef is bleaching.

The Secret Service has arrested suspects accused of counterfeiting coins from 1915 valued at $50,000 each. The students act as a forensic scientist to investigate the crime scene and...

As an agricultural scientist, students help a strawberry farmer who is having problems with low fruit production. Students learn about the factors involved in fruit production including...

Adjust the mass and velocity of two gliders on a frictionless air track. Measure the velocity, momentum, and kinetic energy of each glider as they approach each other and collide....

Measure the time required to write a word when the mouse behaves in a normal fashion and when the direction of motion is reversed from left to right, up to down, or both. Run several...

Apply ratios and proportions to find the weight of a person on the moon (or on another planet). Weigh an object on Earth and on the moon and weigh the person on Earth. Then set up and solve...

Observe the sex ratios of birds and geckos as they hatch in an incubator. Vary the temperature of the incubator and measure the percentages of male and female hatchlings to determine if...

An insulated beaker of hot water is connected to a beaker of cold water with a conducting bar, and over time the temperatures of the beakers equalize as heat is transferred through the bar....

Study the thickness of birds' beaks over a five-year period as you control the yearly rainfall on an isolated island. As the environmental conditions change, the species must adapt (a...

Control the intensity of red, green, and blue spotlights. Additive colors can be observed where the spotlights overlap. The RGB value of any point can be measured. Just about any color can...

Place a pan on the end of a hanging spring. Measure how much the spring stretches when various masses are added to the pan. Create a graph of displacement vs. mass to determine the spring...

Pour water on a variety of sediment samples to find how much water can be absorbed by the sample (porosity) and how easily water flows through the sample (permeability).

Drop a chunk of material in a beaker of water and observe whether it sinks or floats. Cut the chunk into smaller pieces of any size, and observe what happens as they are dropped in the...

Label a diagram that illustrates the anatomy of a flower, and understand the function of each structure. Compare the processes of self pollination and cross pollination, and explore how...

Observe the motions of the Earth, Moon and Sun in three dimensions to investigate the causes and frequency of eclipses. Observe Earth's shadow crossing the Moon during a lunar eclipse, and...

Use a three dimensional view of the Earth, Moon and Sun to explore seasonal changes at a variety of locations. Strengthen your knowledge of global climate patterns by comparing solar...

Build compound circuits with series and parallel elements. Calculate voltages, resistance, and current across each component using Ohm's law and the equivalent resistance equation. Check...

Measure the height and velocity of two objects connected by a massless rope over a pulley. Observe the forces acting on each mass throughout the simulation. Calculate the acceleration of...

Observe a chemical reaction with and without a catalyst. Determine the effects of concentration, temperature, surface area, and catalysts on reaction rates. Reactant and product...

Observe evolution in a fictional population of bugs. Set the background to any color, and see natural selection taking place. Compare the processes of natural and artificial selection....

Derive an equation to calculate the frequency of an oncoming sound source and a receding sound source. Also, calculate the Doppler shift that results from a moving observer and a stationary...

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Learn Kepler's three laws of planetary motion by examining the orbit of a planet around a star. The initial position, velocity, and mass of the planet can be varied as well as the mass of...

Observe light rays that pass through a convex or concave lens. Manipulate the position of an object and the focal length of the lens and measure the distance and size of the resulting image.

Observe the wave fronts produced by four closely-spaced emitters. The spacing and phase shift of each wave source can be adjusted, as well as the wave velocity. With all four sources you...

Investigate how an inclined plane redirects and reduces the force pulling a brick downward, with or without friction. A toy car can apply a variable upward force on the brick, and the...

Gain an understanding of high, low, spring, and neap tides on Earth by observing the tidal heights and the position of the Earth, Moon, and Sun. Tidal bulges can be observed from space, and...

Learn about standard symbols used in meteorology to construct weather maps. Rain, sleet, snow, temperature, cloud cover, wind speed and direction, and atmospheric pressure can all be...

Shine sunlight through a prism and use a thermometer to measure the temperature in different regions of the spectrum. The thermometer can be dragged through the visible spectrum and beyond....

Create a graph of a runner's position versus time and watch the runner run a 40-meter dash based on the graph you made. Notice the connection between the slope of the line and the velocity...

Create a graph (bar graph, line graph, pie chart, or scatter plot) based on a given data set. Title the graph, label the axes, and choose a scale. Adjust the graph to fit the data, and then...

In 1915, Alfred Wegener proposed that all of Earth's continents were once joined in an ancient supercontinent he called Pangaea. Wegener's idea of moving continents led to the modern theory...

Every substance has unique transition points, or temperatures at which one phase (solid, liquid, or gas) transitions to another. Use a realistic melting point apparatus to measure the...

Explore examples of nuclear fusion and fission reactions. Follow the steps of the proton-proton chain, CNO cycle, and fission of uranium-235. Write balanced nuclear equations for each step,...

Explore how sex cells are produced by the process of meiosis. Compare meiosis in male and female germ cells, and use crossovers to increase the number of possible gamete genotypes. Using...

Compare average temperatures, precipitation, humidity, and wind speed for a variety of locations across the globe. Explore the influence of latitude, proximity to oceans, elevation, and...

Understand the definition of a mole and determine the Avogadro constant by adding atoms or formula units to a balance until the mass in grams is equal to the atomic or formula mass....

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In this follow-up to Fast Plants® 1 - Growth and Genetics, continue to explore inheritance of traits in Wisconsin Fast Plants. Infer the genotype of a "mystery P2 parent" of a set of Fast...

See how muscles, bones, and connective tissue work together to allow movement. Observe how muscle contraction arises from the interactions of thin and thick filaments in muscle cells. Using...

Observe how photoreceptors on the retina are stimulated by different colors of light. Determine that cone cells are stimulated by specific colors of light and enable us to see color, while...

As a medical toxicologist, students learn about cell respiration to save the life of a CIA agent that has been poisoned.

As an acoustic engineer, students will work with an urban planner to learn how noise pollution impacts a community. Students will develop a system model to test design solutions. Wave...

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Try to get a hole in one by adjusting the velocity and launch angle of a golf ball. Explore the physics of projectile motion in a frictional or ideal setting. Horizontal and vertical...

Investigate elastic collisions in two dimensions using two frictionless pucks. The mass, velocity, and initial position of each puck can be modified to create a variety of scenarios.

Explore the concepts of limiting reactants, excess reactants, and theoretical yield in a chemical reaction. Select one of two different reactions, choose the number of molecules of each...

Within this simulated region of land, daytime's rising temperature and the falling temperature at night can be measured, along with heat flow in and out of the system. The level of...

Perform experiments with several seed types to see what conditions yield the highest germination (sprouting) rate. Three different types of seeds can be studied, and the temperature, water...

Perform experiments with a pendulum to gain an understanding of energy conservation in simple harmonic motion. The mass, length, and gravitational acceleration of the pendulum can be...

Using four beakers of liquids with known densities, estimate the density of a variety of objects. Place each object into each beaker to see whether it sinks or floats, and then use this...

Move spots of yellow, cyan, and magenta pigment on a white surface. As the colors overlap, other colors can be seen due to color subtraction. The color of most things you see--such as cars,...

Manipulate the magnitudes and directions of two vectors to generate a sum and learn vector addition. The x and y components can be displayed, along with the dot product of the two vectors.

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Explore the motion of particles as they bounce around from one side of a room to the other through an adjustable gap or partition. The mass of the particles can be adjusted, as well as the...

Investigate the properties of an ideal gas by performing experiments in which the temperature is held constant (Boyle's Law), and others in which the pressure remains fixed (Charles's Law)....

Learn about standard symbols used in meteorology to construct weather maps. Rain, sleet, snow, temperature, cloud cover, wind speed and direction, and atmospheric pressure can all be...

Go through the process of synthesizing proteins through RNA transcription and translation. Learn about the many steps involved in protein synthesis including: unzipping of DNA, formation of...

Move the Earth's crust at various locations to observe the effects of the motion of the tectonic plates, including volcanic eruptions. Information about each of the major types of plate...

Drag two charged particles around and observe the Coulomb force between them as their positions change. The charge of each object can be adjusted, and the force is displayed both...

Investigate how calorimetry can be used to find relative specific heat values when different substances are mixed with water. Modify initial mass and temperature values to see effects on...

Create the electron configuration of any element by filling electron orbitals. Determine the relationship between electron configuration and atomic radius. Discover trends in atomic radii...

Adjust the levels of clothing, perspiration, and exercise to maintain a stable internal temperature as the external temperature changes. Water and blood sugar levels need to be replenished...

Observe light rays that reflect from a convex or concave mirror. Manipulate the position of an object and the focal length of the mirror and measure the distance and size of the resulting...

Try to click your mouse once every 2 seconds. The time interval between each click is recorded, as well as the error and percent error. Data can be displayed in a table, histogram, or...

Study the thickness of birds' beaks over a five year period as you control the yearly rainfall on an isolated island. As the environmental conditions change, the species must adapt (a...

Observe the sex ratios of birds and geckos as they hatch in an incubator. Vary the temperature of the incubator and measure the percentages of male and female hatchlings to determine if...

Apply ratios and proportions to find the weight of a person on the moon (or on another planet). Weigh an object on Earth and on the moon and weigh the person on Earth. Then set up and solve...

Measure the mass and volume of a variety of objects, then place them into a beaker of liquid to see if they float or sink. Learn to predict whether objects will float or sink in water based...

Mix the primary colors of light by using red, green, and blue lights. Use pieces of colored glass to filter the light and create a wide variety of colors. Determine how light is absorbed...

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Observe the tilt of Earth's axis and the angle that sunlight strikes Earth on June 21 and December 21. Compare day lengths, temperatures, and the angle of the Sun's rays for any latitude....

Use unit conversion tiles to convert from one unit to another. Tiles can be flipped to cancel units. Convert between metric units or between metric and U.S. customary units. Solve distance,...

Explore the abiotic factors that affect Caribbean coral reefs. Many factors can be manipulated in this simplified reef model, including ocean temperature and pH, storm severity, and input...

Have you ever used a glove warmer to keep your hands warm? How about an instant cold pack to treat an injury? In the Feel the Heat Gizmo, create your own hot and cold packs using various...

Explore the causes of convection by heating liquid and observing the resulting motion. The location and intensity of the heat source (or sources) can be varied, as well as the viscosity of...

Combine various metal and nonmetal atoms to observe how the electronegativity difference determines the polarity of chemical bonds. Place molecules into an electric field to experimentally...

Concussion rates in youth impact sports are high despite the use of helmets. In this STEM case, students act as materials scientists to learn about the physics behind concussions and helmet...

Try to estimate the passage of time by selecting a time interval, clicking the Start button, and clicking Stop when you think the interval has passed. The estimate and percent error are...

Drop objects in a beaker that is filled with water, and measure the water that flows over the edge. Using Archimedes' principle, determine the density of objects based on the amount of...

A falling cylinder is attached to a rotating propeller that stirs and heats the water in a beaker. The mass and height of the cylinder, as well as the quantity and initial temperature of...

Adjust the concentration of a solute on either side of a membrane in a cell and observe the system as it adjusts to the conditions through osmosis. The initial concentration of the solute...

Measure the position, velocity, and acceleration (both components and magnitude) of an object undergoing circular motion. The radius and velocity of the object can be controlled, along with...

Construct a DNA molecule, examine its double-helix structure, and then go through the DNA replication process. Learn how each component fits into a DNA molecule, and see how a unique,...

Pith balls with positive, negative, or no electrical charge are suspended from strings. The charge and mass of the pith balls can be adjusted, along with the length of the string, which...

Solve problems in chemistry using dimensional analysis. Select appropriate tiles so that units in the question are converted into units of the answer. Tiles can be flipped, and answers...

Set the initial percentages of three types of parrots in a population and track changes in genotype and allele frequency through several generations. Analyze population data to develop an...

Observe the movement of particles of an ideal gas at a variety of temperatures. A histogram showing the Maxwell-Boltzmann velocity distribution is shown, and the most probable velocity,...

Fire a banana cannon at a monkey in a tree. The monkey drops from the tree at the moment the banana is fired from the cannon. Determine where to aim the cannon so the monkey catches the...

Within this simulated region of land, daytime's rising temperature and the falling temperature at night can be measured, along with heat flow in and out of the system. The amount of...

Use data from up to three weather stations to predict the motion of a hurricane. The wind speed, wind direction, cloud cover and air pressure are provided for each station using standard...

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Study the production and use of gases by plants and animals. Measure the oxygen and carbon dioxide levels in a test tube containing snails and elodea (a type of plant) in both light and...

Use dichotomous keys to identify and classify five types of organisms: California albatrosses, Canadian Rockies buttercups, Texas venomous snakes, Virginia evergreens, and Florida...

Use the Unit Conversions Gizmo to explore the concepts of scientific notation and significant digits. Convert numbers to and from scientific notation. Determine the number of significant...

In this followup to the Coral Reefs 1 - Abiotic Factors activity, investigate the impacts of fishing, disease, and invasive species on a model Caribbean coral reef. Many variables can be...

Weathering is the breakdown of rock at Earth's surface through physical or chemical means. Students will learn about the different types of mechanical and chemical weathering, then use a...

Exothermic chemical reactions release energy, while endothermic reactions absorb energy. But what causes some reactions to be exothermic, and others to be endothermic? In this simulation,...

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Explore trends in atomic radius, ionization energy, and electron affinity in the periodic table. Measure atomic radius with a ruler and model ionization energy and electron affinity by...

Learn about molecular polarity and how polarity gives rise to intermolecular forces. Measure four macroscopic properties of liquids (cohesion, adhesion, surface tension, and capillary...

Explore relationships between amount, temperature, pressure, and volume for an ideal gas in a chamber with a moveable piston. Discover rules of proportionality contained in Boyle's law,...

As a physician assistant, students must learn about diffusion to save the life of a person poisoned by chlorine gas that was released into a small town following a train crash.

As a pediatrician, students learn about genes and protein synthesis to try to help a baby girl named Lucy who has an immunodeficiency disease.

The Secret Service has arrested suspects accused of counterfeiting coins from the year 1915 valued at $50,000 each. The students act as a forensic scientist to investigate the crime scene...

There has been an outbreak of legionnaires’ disease in a small town. This disease is caused by legionella bacteria that proliferate in contaminated water supplies. Students take on the role...

The Bay Area of California experiences frequent earthquakes. Earthquakes are unpredictable and cause enormous damage that leads to casualties. Students take on the role of an earth...

Investigate the decay of a radioactive substance. The half-life and the number of radioactive atoms can be adjusted, and theoretical or random decay can be observed. Data can be interpreted...

Use data from up to three weather stations to predict the motion of a hurricane. The wind speed, wind direction, cloud cover and air pressure are provided for each station using standard...

Test the acidity of common substances using pH paper. Materials including soap, lemon juice, milk, and oven cleaner can be tested by comparing the color of pH strips to a standard scale.

Observe the effect of predators on a population of parrots with three possible genotypes. The initial percentages and fitness levels of each genotype can be set. Determine how initial...

One of the simplest machines is a see-saw lever. Place up to eight objects on the lever at different locations and try to balance it. Calculate net torque and moment of inertia based on the...

Compare the skulls of a variety of significant human ancestors, or hominids. Use available tools to measure lengths, areas, and angles of important features. Each skull can be viewed from...

Measure the strength and direction of the magnetic field at different locations in a laboratory. Compare the strength of the induced magnetic field to Earth's magnetic field. The direction...

Measure the quantity of a known solution needed to neutralize an acid or base of unknown concentration. Use this information to calculate the unknown concentration. A variety of indicators...

Observe how reactants and products interact in reversible reactions. The initial amount of each substance can be manipulated, as well as the pressure on the chamber. The amounts,...

Explore how river erosion affects landscapes in the short term and over long periods of time. Describe the features of mountain streams and meandering rivers, and use a floating barrel to...

As a national park ranger, students must restore the ecosystem of a park back to normal. They interact with populations of many organisms including wolves, deer and bees. Students learn the...

In the role of a physician assistant, students help a young man, named Anthony, who has Type II diabetes and high blood pressure. Students must make a diagnosis and then must apply the...

As a geneticist in an animal hospital, students learn about genetic changes in meiosis to determine the reason why a male cat can have calico fur coloring.

A respiratory physiologist is concerned about the number of asthma attacks in children within her community. On certain days, the number is higher than the respiratory physiologist might...

Students acting as spacecraft navigation engineers apply their knowledge of Newton’s Third Law of Motion to launch a communication satellite into a stable orbit around Earth. When students...

Investigate the energy and motion of a block sliding down an inclined plane, with or without friction. The ramp angle can be varied and a variety of materials for the block and ramp can be...

Release a lytic virus in a group of cells and observe how cells are infected over time and eventually destroyed. Data related to the number of healthy cells, infected cells, and viruses can...

Test the acidity of many common everyday substances using pH paper (four color indicators). Materials including soap, lemon juice, milk, and oven cleaner can be tested by comparing the...

Place masses on a circular table and see how fast it spins when struck by a piston. Discover the relationships between angular velocity, mass, radius and moment of inertia for collections...

Control a simulated person running on a treadmill. Your challenge is to use clothing, exercise, and sweat to maintain a constant body temperature as air temperature goes up and down....

Explore how a changing magnetic field can induce an electric current. A magnet can be moved up or down at a constant velocity below a loop of wire, or the loop of wire may be dragged in any...

Explore erosion in a simulated 3D environment. Observe how the landscape evolves over time as it is shaped by the forces of flowing water. Vary the initial landscape, rock type,...

The Coriolis effect causes winds to be deflected as they move across Earth's surface, resulting in circular patterns of winds. This effect is caused by two factors, Earth's rotation and...

An infant on a farm has blue baby syndrome. As an EPA environmental engineer, students must find the cause of the baby's illness. Using environment data, students learn the importance of...

Using an earthquake recording station, learn how to determine the distance between the station and an earthquake based on the time difference between the arrival of the primary and...

Scan the DNA of frogs to produce DNA sequences. Use the DNA sequences to identify possible identical twins and to determine which sections of DNA code for skin color, eye color, and the...

Observe the five main types of nuclear decay: alpha decay, beta decay, gamma decay, positron emission, and electron capture. Write nuclear equations by determining the mass numbers and...

Observe and compare objects of different shapes as they roll or slide down an inclined plane. Compare the percentages of translational and rotational kinetic energy for each object, and see...

Observe how reactants and products interact in reversible reactions. The amounts of each substance can be manipulated, as well as the pressure on the chamber. This lesson focuses on partial...

Explore how a fertilized cell develops into an embryo, a fetus, and eventually an adult organism. Compare embryo development in different vertebrate species and try to guess which embryo...

Based on the similarities and differences between different organisms, create branching diagrams called cladograms to show how they are related. Use both morphological data (physical...

As a national park ranger, students must restore the ecosystem of a park back to normal. They interact with populations of many organisms including wolves, deer and bees. Students learn the...

As a bee scientist, students help a honey farm that has low honey production due to wasps. Students learn about bees, heredity and traits to determine which traits will help the bees defend...

Locate the epicenter of an earthquake by analyzing seismic data from three recording stations. Measure difference in P- and S-wave arrival times, then use data from the Earthquakes 1 -...

Sort and pair the images of human chromosomes obtained in a scan. Find differences in the scans of the various patients to find out specific things that can cause disease, as well as...

Shoot a beam of light at a metal plate in a virtual lab and observe the effect on surface electrons. The type of metal as well as the wavelength and amount of light can be adjusted. An...

Drag blocks onto a two-dimensional surface and observe the effects on the center of mass. Use a grid to calculate the coordinates of the center of mass. Investigate predefined shapes or...

As a national park ranger, students must restore the ecosystem of a park back to normal. They interact with populations of many organisms including wolves, deer and bees. Students learn the...

As a veterinarian, students help a young calf, named Clark, who is having seizures. To determine the cause, the students fly into Clark's brain to learn about osmosis and apply their...

As an agricultural scientist, students help a strawberry farmer who is having problems with low fruit production. Students learn about the factors involved in fruit production including...

A farmer in Africa is having problems with elephants eating her corn and cotton crops. As a wildlife biologist, students learn about animal group behavior and relationships of elephants and...

A farmer in Africa is having problems with elephants eating her corn and cotton crops. As a wildlife biologist, students learn about animal group behavior and relationships of elephants and...

There has been an outbreak of legionnaires’ disease in a small town. This disease is caused by legionella bacteria that proliferate in contaminated water supplies. Students take on the...

Thawing permafrost threatens the stability of critical infrastructure in the Arctic community of Frostville, Alaska. Students take on the role of a civil engineer to design heat transfer...

People are getting sick after swimming in the Dogwood River. The student acts as a microbiologist to monitor bacteria populations, construct a model of how pollution enters the river, and...

Fire photons to determine the spectrum of a gas. Observe how an absorbed photon changes the orbit of an electron and how a photon is emitted from an excited electron. Calculate the...

As a veterinary technician, students learn about enzymes to help a dog that has been eating normally but is losing a lot of weight.

Mussel farmers in the Arctic Ocean have reported problems with their mussels. They have noticed that the mussel shells have eroded and become brittle. Students take on the role of a marine...

As a bee scientist, students help a honey farm that has low honey production due to wasps. Students learn about bees, heredity and traits to determine which traits will help the bees defend...

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An important fish species, the American Shad, has disappeared from the James River in Virginia. Students take on the role of a junior River Watch member to investigate the shad population’s...

Shoot a stream of photons through a container of hydrogen gas. Observe how photons of certain energies are absorbed, causing the electron to move to different orbits. Build the spectrum of...

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Paanee, a city in Northeast India, has been experiencing higher rates of flooding than normal. This surge in flooding has been caused by an increase in the hydrologic cycle’s activity....

Lake City's latest heat wave has more people in the hospital than ever before. Juan, a local student admitted to the hospital, lives in one of the hottest neighborhoods in the city....