In this free science fair project, learn how to separate salt from water using heat. A great science project for elementary school kids.

In this sound experiment children listen for differences as they tap on a bag of air, a bag of water, and a wooden block held up to their ears.

In this air pressure science experiment with a balloon and a jar, children will use heat to create a partial vacuum and suck a balloon into a jar.

Using an empty tennis ball can and a swimming pool, you will determine if it's possible to have a conversation under water.

How does a kazoo, the strings of a guitar, or the speaker of a radio make sound? The purpose of this science fair project is to show how vibration makes sound.

This classic children's game demonstrates how sound travels through air vs. through a solid.

This classic children's game-connecting two cups with a string-demonstrates sound's ability to travel through air vs through a solid.

This project demonstrates the correspondence between the volume of water displaced by a submerged object and the volume of the object displacing it.

What causes sound? Here's a simple science experiment that adds a visual element to the science of sound to help kids better understand this tricky concept.

Put your second grade scientist to work this Fourth of July with our colorful "liquid fireworks" project!

Here's a fun math and science activity: help your child explore four different kinds of measurement, using their hand and a few simple household tools.

What is elasticity? Students will investigate how this concept applies to bouncing ball physics by testing the bounces of balls made out of different materials.