100's Day

What does 100 look like? Sound like? Feel like? In this video from Curious George, explore the many ways to measure 100 things.

Accessibility features: Caption

3D Space: Illusion or Reality?

This video excerpt from NOVA’s "The Fabric of the Cosmos: What Is Space?" reveals new data about black holes that has led to a new idea about the universe: Instead of everything being a three-dimensional object, it’s possible that everything is actually just a hologram.

Accessibility features: Caption, Transcript

Accidental Discoveries

This lesson will help the students understand that science theories change in the face of new evidence, but those changes can be slow in coming.

Accidental Discoveries

This segment from Swift: Eyes through Time traces the history military officers and engineers discovering a strange phenomenon in the sky that astronomers now know are gamma-ray bursts.

Accessibility features: Caption

AC / DC: What's the Difference?

This animated essay from the American Experience Web site explains the difference between alternating and direct electric current and offers in-depth explanations about the role played by a battery, light bulb, wire, and generator.

Acids and Bases: Cabbage Juice Indicator

In this video segment, the ZOOM cast demonstrates how to use cabbage juice to find out if a solution is an acid or a base.

Accessibility features: Caption

Acids and Bases: Kitchen Chemistry

In this interactive activity from the ZOOM Web site, search for chemistry clues and experiment with acids and bases in a virtual kitchen.

Acids and Bases: Making a Film Canister Rocket

In this video segment, ZOOM cast members mix different amounts of baking soda and vinegar to see which combination produces the most carbon dioxide for launching a film-canister rocket.

Accessibility features: Caption

Acids and Bases: Testing Rocket Cars

In this ZOOM video segment, cast members make bottle rocket cars using lemon juice and baking soda, and experiment with different ways of launching the cars.

Accessibility features: Caption

Acids and Bases: Testing Rockets

What happens when you mix baking soda and lemon juice? Watch the ZOOM cast launch a rocket using kitchen chemistry.

Accessibility features: Caption

Aerodynamics: What Causes Lift?

How does an airplane stay aloft when upside down? This media-rich essay from the NOVA Web site offers an explanation based on Newton's third law of motion.

Airborne Wind Energy

The strongest and most consistent winds are found in the jet stream as high as 30,000 feet above the earth. In this video from QUEST produced by KQED, learn about the benefits and challenges of wind energy.

Air Is Matter

This collection of still images presents different ways to visualize air, from billowing sails to windblown hair to tornadoes.

Air Is Matter

Students investigate air and how it is something that occupies space, has mass, and exerts pressure.

Airplanes: Designing for Stealth

Explore this NOVA interactive activity to see how engineers have modified a military plane's sound, shape, and heat emissions to minimize detection.

Air Power: Experimenting with Balloons

In this video segment adapted from ZOOM, cast members experiment with the amount of air expelled first from a balloon, then through a straw attached to it, and see how both affect a balloon's behavior.

Accessibility features: Caption

Air Power: Making a Hovercraft

In this video segment adapted from ZOOM, cast members make their own hovercraft and demonstrate how the air leaking out of a balloon can make a plastic plate hover above a table.

Accessibility features: Caption, Transcript

Amplitude

This interactive activity adapted from the University of Utah's ASPIRE Lab shows how a pendulum's amplitude changes as you set it swinging from different distances from its axis, and how the amplitude of a sound wave changes as you adjust the volume.

Anatomy of a Firework

There's more to a fireworks display than meets the eye. This interactive activity from the NOVA Web site looks at the technology behind each burst of light.

Arch Bridge

This video segment adapted from Building Big illustrates the strength of the arch in bridge design and construction.

Accessibility features: Caption