This video segment adapted from Shedding Light on Science describes how astronomical distances can be measured in units of light-years, and how the finite speed of light allows astronomers to study how the universe looked long ago.

This video segment adapted from Shedding Light on Science demonstrates the law of reflection by showing how light energy is reflected off both smooth and rough surfaces at predictable angles.

This video segment from a WPSU documentary Liquid Assets connects public health to the availability of clean and safe drinking water and elaborates on the threats our bodies face due to increasing kinds and quantities of pollutants.

This Nature video shows the migratory patterns and habits of the Rufous hummingbird.

What is it that distinguishes a living organism from a nonliving object? This collection of images presents examples that aren't as clear-cut as one might think, enticing students to question the meaning of life.

In this video segment adapted from the Alaska Native Heritage Center, discover the connections between Alaska Native subsistence culture and the natural cycle of the seasons.

This video, adapted from material provided by the ECHO partners, illuminates how living on the coast affects individuals and communities, particularly humans' interrelationships with natural resources.

This video segment of Swift: Eyes through Time provides concrete examples to explain the concept that distance in space equals distance in time.

This video from KET traces the energy transformations that occur when coal is burned to produce electricity. Some of the mechanical processes are also described.

In this adapted ZOOM video segment, cast members get hands-on in the recycling process by using old newspapers to make new paper.

In this video segment adapted from ZOOM, cast members make a seismometer and experiment with different ways to make it register movement.

This video adapted from NASA explains how a magnetometer determines magnetic fields around planets.

This video segment from NOVA: "The Mystery of Animal Pathfinders" explores how the migratory patterns of shorebirds have evolved to coincide with the spawning of horseshoe crabs.

This simulation provides a realistic virtual mass-and-spring laboratory. Users can explore spring motion by manipulating stiffness of the spring and mass of the hanging weight. Concepts of Hooke's Law and elastic potential energy are further clarified through charts showing kinetic, potential, and thermal energy for each spring. This item is part of a larger collection of simulations developed by the Physics Education Technology project (PhET). The simulations are animated, interactive, and game-like environments in which students learn through exploration. All of the sims are freely available from the PhET website for incorporation into classes.

Two astronauts aboard the International Space Station (ISS) describe mass and weight and the differences between the two in this video from NASA’s Teaching From Space initiative.

This video segment adapted from Discovering Women profiles Fermilab physicist and Harvard professor Melissa Franklin.

All animals develop and grow over time. The animals in this video segment, however, undergo very dramatic changes on their way to adulthood -- a developmental process known as metamorphosis.

Learn about an important physics experiment that uses an invention that manipulates light in this interactive activity adapted from NASA.

In this video from DragonflyTV, Tiana and Sammy measure, record, and analyze the results of a drop box test to find out how everyday items behave in microgravity.

This video segment from NOVA: "The Mystery of Animal Pathfinders" explores the migratorial exploits of monarch butterflies.