In this Nature video, learn about the extraordinary impact that birds have on the agriculture of a small Indian community.
In this video segment, adapted from NOVA, Dr. Judah Folkman uses the scientific method to discover how cancer cells induce the formation of new blood vessels, which in turn nourish those cancer cells.
This interactive feature from the NOVA "Surviving Denali" Web site details the variety of ways the body can fail while climbing a high-altitude peak.
Throughout the day, your nervous system monitors and makes endless adjustments to your body's basic systems -- all to keep you alive. This interactive feature illustrates the complexity of such a task.
This video segment, adapted from NOVA scienceNOW, presents basic concepts of physics behind booming sand dunes. See how surface tension affects potential and kinetic energy and how it all works together to create sound.
Which part of your brain controls your ability to swallow? Your instinct to survive? And how do all the brain's parts function cooperatively? Find out with this interactive feature from the NOVA: "Coma" Web site.
In this interactive activity from the Building Big Web site, use your knowledge of bridge design to match the right bridge to the right location in a fictitious city.
In this video segment adapted from A Science Odyssey, learn about bubonic plague and how city officials in San Francisco tried to contain its spread in the early 1900s..
In this interactive activity from Shedd Aquarium, build a fish and then release it into the reef to search for food and evade predators. Try different combinations and observe how each kind of fish has unique adaptations that help it survive in its habitat.
In this video segment adapted from ZOOM, the cast shows how the 34 steps in their Rube Goldberg invention use everything from gravity to carbon dioxide gas in order to accomplish one simple task: pouring a glass of milk.
In this video segment from ZOOM, Jillian explains how her simple machine uses marbles, levers, flowing sand, and a spinning wheel to water a plant.
In this video segment from PEEP and the Big Wide World, children make a dam with dirt, sticks, and stones to try to stop the flow of water.
How do you build a tunnel 32 miles long -- under water? This video segment adapted from Building Big, follows the construction of the Channel Tunnel (nicknamed "Chunnel"), the engineering wonder that connects England to France.
This illustrated demonstration from the NOVA Web site explains the concepts of buoyancy and density by showing what happens when different kinds of wood blocks are dropped in water.
This interactive brainteaser from the NOVA Web site challenges you to explain the behavior of a helium-filled balloon in a moving car.
This interactive brainteaser from the NOVA Web site challenges you to figure out what happens to the water level when a rock is resting in a boat and when it is submerged in water.
This interactive brainteaser from the NOVA Web site challenges you to figure out what causes an object to sink.
In this Cyberchase video segment, the CyberSquad must estimate the measurements of Spout the Whale in order to find a cage that will fit him.Ű_í_
In this video segment from Cyberchase, Inez and Lucky figure out how to keep track of the number of clones as they continue to multiply.
In this video segment from Cyberchase, the CyberSquad measures Judge Trudy's land claim by using tarps, fence posts and a grid made with rope.