Use reusable, recyclable materials--along with a dose of imagination--to build a castle with first grade geometrical forms.

In this activity, young learners will make a balance using a plastic hanger and weigh a variety of small objects using candy corn.

This science fair project idea produces sounds by creating vibrations using different objects.

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

Learn to solve a crime scene investigation using an important forensics tool: oblique lighting.

In this physics project, learn about the relationship between light intensity and distance using a laser pointer, flashlight, and graph paper!

Amaze your kids by separating a salt and pepper mixture using an "electric spoon" charged with wool.

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

Help your second grade scientist explore the timely topic of wind speed using a version of the classic Beaufort Scale.

Teach your first grade scientist the difference between liquids and solids using maple syrup.

This 4th of July, explore fourth grade science and make some safe fireworks in your own backyard using soda pop!

Your child will do a fun science experiment using soap and pepper flakes to help understand the concepts of water molecules and the surface tension of water.

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.

Think you can blow up a balloon without using your mouth? This isn't just a cool trick, it's also a great way to introduce chemistry and biology concepts.

Make your own helicopter using a paper clip and a sheet of paper. Hold the spinner up in the air, let it go, and watch it spin gracefully to the ground.

Have your child build his own mini waterfall, and help him develop his planning, problem solving, and architectural skills.

In this fun science fair project idea learn about universal solvents and solutes and find out the solubility of several common liquid substances.

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

Play this flashlight game with your child to teach him about objects that are transparent, translucent, and opaque.

In this science fair project, young children discover what happens when two fluids that have different densities get together.

Blanket forts are a kid classic! Let your child create a âfortress of solitudeâ on his own for reading, telling scary stories or for cozy cocooning.

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

This science fair project idea experiments with spinning color wheels and optical illusions.

Help your child get a grasp on what it was like to build gigantic ancient structures with this easy engineering activity about science and physics.

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.

How does the size of a vibrating surface affect the pitch of a drum? Learn about drum size and pitch with this easy science fair project idea.

Inspire your child to put on her engineer hat for the day, as she builds her very own, double-decker bridge.

On the next chilly, winter day, invite your fifth grader to make a hand warmer by experimenting with the loaded combination of a few natural ingredients.

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.

Air invisible; it doesn't make sounds; you can't pick it up and throw it. So how do we know it exists? Help your second grade scientist figure it out.