In this video adapted from the Arctic Athabaskan Council, learn how warmer temperatures in the Arctic are transforming the landscape, triggering a host of effects such as permafrost thawing and insect infestations.

This video segment adapted from NASA describes the basic characteristics of our star, the Sun.

In this video segment adapted from NOVA, scientists are on the hunt for tornadoes. Using Doppler radar, they gather data in the hopes of solving the mystery of how tornadoes form.

In this interview filmed for Evolution: "Darwin's Dangerous Idea," biologist Chris Schneider discusses the relationship between conservation and speciation.

This video adapted from KTOO takes a look at Earth's warming and cooling cycles and the current atypical trend of warming that is impacting the glaciers in Alaska's Inside Passage.

This interactive resource adapted from the National Park Service describes the different kinds of sediments that make up coastlines, with a focus on the variety in color, size, and sorting.

This interactive resource adapted from the National Park Service describes the many forces that affect shorelines, including tides, weathering, erosion, and deposition.

Watch the ZOOM cast find out how many balloons filled with air and then with water are required to support the weight of a cast member.

In this video segment, members of the ZOOM cast experiment by bending and folding sheets of paper into various shapes to see which shape will support the weight of a heavy book.

In this video segment from ZOOM, Hillary, from Randolph, MA, takes us on a tour of the columns in her neighborhood.

In this text excerpted from chapter 3, Struggle for Existence, of Charles Darwin's On the Origin of Species, Darwin draws on firsthand and historical information for his observations about evolution.

The levels of contaminants found in particular animals vary widely depending on where they fit into the Arctic food chain, as described in this video segment adapted from LOKE Films and the Arctic Monitoring and Assessment Programme.

In this video segment adapted from LOKE Films and the Arctic Monitoring and Assessment Programme, learn how human populations in the Arctic are affected by industrial contaminants in the food chain.

This video segment adapted from the Atmospheric Radiation Program explains the differences in the formation of tropical convective cloud systems over islands and over the ocean.

In this video segment adapted from ZOOM, two solar cookers are tested against a control to see which can cook a "s'more" faster.

In this video segment, ZOOM guest Cassie takes us on a tour of the coral reef near her home in Key Largo, Florida, and points out some of its unique features.

This interactive activity from ChemThink takes a closer look at a covalent bond--how it is formed and how the sharing of two electrons can keep atoms together.

Students learn how DNA fingerprinting has been used in criminal investigations and discuss the limitations of and problems with DNA testing.

In this interactive activity from the Building Big Web site, investigate dams in distress and decide if they should be repaired, removed, or left alone.

This video segment from Evolution: "Darwin's Dangerous Idea," together with interviews with Daniel Dennett and James Moore, depicts Darwin struggling with publicizing his revolutionary theory.