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.

Learn how to make an anemometer with step-by-step instructions in this cool science fair project idea for 4th grade.

How powerful is the reaction between baking soda and vinegar? Find out here!

Your fourth grader will be astonished to discover the significance and intricacies of his spine as he builds a model of a human vertebral column.

This interdisciplinary card game will have your third grader working on math facts as he travels through the solar system!

In this activity, your child will learn about a style of gardening that uses moss, also called "kokedama."

The purpose of this science fair project is to demonstrate how yeast, a fungus, causes bread to rise.

Create a brush pile to help wintering wildlife stay warm and cozy through the winter.

Help your child plant a "tea garden": a garden made of herbs for making teas.

In this science fair projects, students will grow out the bacteria that collect on air conditioner filters.

This science fair project examines how seeds hitchhike on animals and clothing.

Determine whether butterflies like to drink sugar water, salt water, or plain water.

In this Halloween-themed activity, young learners will find out what happens when they mix two household items together to create a surprising chemical reaction.

The objective of this science fair project is to observe the differences in heat absorption for darker colors vs. lighter colors.

Excite your fourth grader by recreating ancient Viking myths. This miniature longboat will explore the principle of water molecules expanding when heated.

Along with being an interesting science activity, dehydrated strawberries are also tasty â and healthy!

This science fair project teaches kids experimental design and how to test if subjects can really sense if they are being watched.

Make some easy homemade yogurt with your young scientist, and see what a few 'live' bacteria can do in the right conditions!

What does a raindrop look like when it splashes on the ground? Is each raindrop unique like snowflakes? Find out how raindrop size varies in this experiment.

How does a flashlight work? Kids will make a complete circuit and explore how voltage contributes to brightness with this science fair project idea.

Do you think you can blow down a sand castle with a mighty wind? Find out which material stands up best to erosion in this erosion experiment.

Magic, science, or household cleanser? Let your second grader decide with this practical, nontoxic chemistry experiment with acids and bases.

Crayons aren't just good for creating colorful masterpieces -- they're also great for science!

Grow potatoes in a plastic bag—easy to grow and harvest, and yummy to eat!

Create a mini plant habitat with your kid to help teach him what it takes to make an ecosystem work.

Celebrate April Fools' Day with a science prank that is sure to amuse...and educate too!

Has your child ever asked you how a submarine works? Here's a simple bathtub project that will make for a hands-on answer.

Help your child create a tasty treat that will demonstrate exactly how frogs survive a freezing season.

Free science fair project idea that examines the differences between cats and dogs. Analyze objective qualities rather than subjective ones.