In this video segment adapted from NOVA, a team of archaeologists and engineers explores different uses of the lever by recreating the engineering feats of the ancient Easter Island peoples.

Three billion years ago single-celled underwater bacteria used sunlight to convert carbon dioxide and water into tiny oxygen bubbles. Soon plants were turning an atmosphere full of volcanic carbon dioxide into oxygen. As we learn in this video segment from Interactive NOVA: "Earth," photosynthesis created a good home for animals and humans, though not for some primitive organisms. They had to retreat to where oxygen couldn't reach them. Join researchers as they search for these organisms, now considered tiny time capsules from a time before there was oxygen on Earth.

How can you lift a heavy metal table using air? In this video segment adapted from ZOOM, cast members succeed in lifting a table using their own breath and a few plastic bags.

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 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 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.

Using paper, shaving cream, and food coloring students marble paper. Using principles of intermolecular forces, students identify which materials are most attracted to other materials and justify their answers with observations from the activity.

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.

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.

Milk is made up of water, fat, and proteins. Each of these molecules have charges and are held together by intramolecular forces. When the dish soap is added to the plate it quickly disperses across the surface as it is attracted to the water molecules and the food coloring is pulled along. This could be used as an anchoring phenomenon on matter, materials, or intramolecular forces.

What determines the concentration of a solution? Learn about the relationships between moles, liters, and molarity by adjusting the amount of solute and solution volume. Change solutes to compare different chemical compounds in water.

In this interactive activity from ChemThink, learn about covalent molecules and how the VSEPR theory predicts the shapes of covalently-bonded molecules.

When is a molecule polar? Change the electronegativity of atoms in a molecule to see how it affects polarity. See how the molecule behaves in an electric field. Change the bond angle to see how shape affects polarity. Need to have JAVA installed to view the Real Molecules pportion of the simulation.

Explore molecule shapes by building molecules in 3D! How does molecule shape change with different numbers of bonds and electron pairs? Find out by adding single, double or triple bonds and lone pairs to the central atom. Then, compare the model to real molecules!

Explore molecule shapes by building molecules in 3D! Find out how a molecule's shape changes as you add atoms to a molecule.