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 the path of the Moon's shadow across Earth's surface during a solar eclipse. The angle of the Moon's orbit can be adjusted, as well as the distance of the Moon from the Earth.

3D Eclipse

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 the path of the Moon's shadow across Earth's surface during a solar eclipse. The angle of the Moon's orbit can be adjusted, as well as the distance of the Moon from the Earth.

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 have the same number of squares. Solve multiplication problems by joining two smaller chocolate bars into a large bar.

Chocomatic (Multiplication, Arrays, and Area)

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 have the same number of squares. Solve multiplication problems by joining two smaller chocolate bars into a large bar.

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 other factors on climate. Observe how animals and plants are adapted to climate and their environment. This lesson uses U.S. customary units.

Comparing Climates (Customary)

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 other factors on climate. Observe how animals and plants are adapted to climate and their environment. This lesson uses U.S. customary units.

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 graph, which has a more step-like appearance.

Compound Interest

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 graph, which has a more step-like appearance.

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 temperature of the room and the initial number of particles. In a real-world context, this can be used to learn about how odors travel, fluids move through gaps, the thermodynamics of gases, and statistical probability.

Diffusion

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 temperature of the room and the initial number of particles. In a real-world context, this can be used to learn about how odors travel, fluids move through gaps, the thermodynamics of gases, and statistical probability.

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 what would happen if some of those organs were eliminated, or if the sequence was changed? Can the digestive system be improved? Find out by designing your own digestive system with the Digestive System Gizmo.

Digestive System

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 what would happen if some of those organs were eliminated, or if the sequence was changed? Can the digestive system be improved? Find out by designing your own digestive system with the Digestive System Gizmo.

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 the body through time. Based on the reaction of the patient, determine the ideal levels of medication. Create a dosage schedule so these levels are maintained through time. Four types of pills, each with a different release pattern and target organ, are available for use.

Drug Dosage

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 the body through time. Based on the reaction of the patient, determine the ideal levels of medication. Create a dosage schedule so these levels are maintained through time. Four types of pills, each with a different release pattern and target organ, are available for use.

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 and dye. Add dye to a container of water, and then add beakers of pure water while removing beakers of dyed water. The amount of dye remaining is recorded after each cycle. The volumes of all containers can be adjusted, as well as the amount of dye used. This provides a good example of exponential decay.

Dye Elimination

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 and dye. Add dye to a container of water, and then add beakers of pure water while removing beakers of dyed water. The amount of dye remaining is recorded after each cycle. The volumes of all containers can be adjusted, as well as the amount of dye used. This provides a good example of exponential decay.

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 water can be adjusted. The temperature of the water is measured as energy is converted from one form to another.

Energy Conversion in a System

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 water can be adjusted. The temperature of the water is measured as energy is converted from one form to another.

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 creatures are producers, consumers, and decomposers. Pictographs and line graphs show changes in populations over time.

Forest Ecosystem

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 creatures are producers, consumers, and decomposers. Pictographs and line graphs show changes in populations over time.

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 fractions that are equivalent to one-half.

Fraction Artist 1 (Area Models of Fractions)

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 fractions that are equivalent to one-half.

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 the area models to shade them. Compare the numbers visually or on a number line.

Fraction, Decimal, Percent (Area and Grid Models)

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 the area models to shade them. Compare the numbers visually or on a number line.

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 velocity vectors can be displayed, as well as the path of the ball. The height of the golfer and the force of gravity are also adjustable.

Golf Range

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 velocity vectors can be displayed, as well as the path of the ball. The height of the golfer and the force of gravity are also adjustable.

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.

Histograms

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.

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 with replacement of the marbles to study independent events, or without replacement to explore dependent events.

Independent and Dependent Events

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 with replacement of the marbles to study independent events, or without replacement to explore dependent events.

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 height.

Mean, Median, and Mode

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 height.

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 meiosis and crossovers, create "designer" fruit fly offspring with desired trait combinations.

Meiosis

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 meiosis and crossovers, create "designer" fruit fly offspring with desired trait combinations.

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, and compare the energy produced in each process.

Nuclear Reactions

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, and compare the energy produced in each process.

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 or Jupiter to determine the effect of gravity.

Pendulum Clock

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 or Jupiter to determine the effect of gravity.

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 the relative humidity and dew point change over the course of a day.

Relative Humidity

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 the relative humidity and dew point change over the course of a day.

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 rectangles and explore how the graph of the rectangles and curve change in response.

Riemann Sum

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 rectangles and explore how the graph of the rectangles and curve change in response.

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.

Rock Classification

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.

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 graph of the quadratic in the real plane.

Roots of a Quadratic

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 graph of the quadratic in the real plane.

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 property can be used to combine variable terms, producing expressions that will help your pet grow up healthy and strong. You'll become a pro at identifying terms that can be combined – even terms with exponents and multiple variables. With enough practice, you and your pet will be ready for the competitive expression eating circuit. Good luck!

Simplifying Algebraic Expressions II

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 property can be used to combine variable terms, producing expressions that will help your pet grow up healthy and strong. You'll become a pro at identifying terms that can be combined – even terms with exponents and multiple variables. With enough practice, you and your pet will be ready for the competitive expression eating circuit. Good luck!

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 long each planet takes to go around the Sun.

Solar System

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 long each planet takes to go around the Sun.

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. Look for unusual features such as redshifted stars, nebulae, and stars with large planets.

Star Spectra

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. Look for unusual features such as redshifted stars, nebulae, and stars with large planets.

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, mean velocity, and root mean square velocity can be calculated. Molecules of different gases can be compared.

Temperature and Particle Motion

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, mean velocity, and root mean square velocity can be calculated. Molecules of different gases can be compared.

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. Plot your find on a zoomable number line map. Can you become a master Treasure Hunter?

Treasure Hunter (Decimals on the Number Line)

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. Plot your find on a zoomable number line map. Can you become a master Treasure Hunter?

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 be recorded over time to determine the time required for the virus to mature within a cell.

Virus Lytic Cycle

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 be recorded over time to determine the time required for the virus to mature within a cell.