In this video segment adapted from NOVA, NASA learns hard lessons from the first American attempt to do work while "walking" in space. The video also explores Newton's third law of motion.

In this video segment adapted from NOVA scienceNOW, MIT engineer Dava Newman is working to replace today's bulky, inflated space suits with a radical, sleek design that may one day allow astronauts to walk easily on Mars.

Coral reefs are often portrayed as brightly lit, bustling underwater marvels full of colorful creatures. This video segment, adapted from NOVA, paints a different picture as it explores the nocturnal behavior of organisms in the reef.

This video segment adapted from the NOW-RAMP 2002 Expedition documents a research expedition to Nihoa Island. It showcases Nihoa's unique birds and plants, the threat posed by invading grasshoppers, and restoration efforts.

Observe the Nisqually Glacier at Mount Rainier in this video segment from NatureScene.

Nitrogen, one of the most abundant elements in the universe, is essential to life. This interactive activity adapted from the University of Alberta provides an overview of the nitrogen cycle.

This video segment adapted from FRONTLINE looks at nuclear fission as an energy source that can be used to generate electricity.

In this lesson designed to enhance literacy skills, students examine the nutritional content of different foods and learn about the health benefits and risks associated with the food choices they make.

This video segment produced for Teachers' Domain features a time-lapse video of clouds forming, changing, and moving across the sky.

This brief video segment produced for Teachers' Domain features time-lapse video of a sunrise and a sunset.

Learn how snowfall happening later in the year than usual is impacting cultural practices in this video segment about climate change adapted from the College of Menominee Nation.

In this video segment adapted from the College of Menominee Nation, tribal members observe lower water levels in lakes and streams and call for global, collaborative solutions to address climate change.

This video segment adapted from Shedding Light on Science illustrates how light changes speed, and thus direction, in a process known as refraction.

This video adapted from KTOO explores the impact of oil contamination on the herring population of Prince William Sound, Alaska, in 1999, 10 years after the Exxon Valdez oil spill.

This video segment adapted from NOVA follows the clean-up effort after the 1989 Exxon Valdez oil spill off the coast of Alaska. Also featured is a marsh where an oil spill occurred 20 years earlier; analysis suggests that environmental damage may last for decades.

In this video segment adapted from the Yukon River Panel, visit fishing communities along the Yukon River and see how Alaska Native peoples exercise stewardship of salmon to ensure that it remains a central food source and cultural touchstone.

Against the backdrop of the devastating 1930's Dust Bowl, this video segment adapted from Interactive NOVA profiles an organic farmer and the techniques he uses to conserve topsoil.

This video segment adapted from NOVA explains the origin of the elements and how scientists use unique element profiles to identify supernova types.

This video segment adapted from NOVA follows the Apollo 15 astronauts as they collect samples of ancient rock from the Moon's crust, whose discovery helps lead to a radical new theory about the Moon's origin.

Have we overstepped Mother Earth's boundaries? What are the consequences? In this video segment adapted from Haskell Indian Nations University, hear a Native perspective on our relationship with the natural environment.