Using a toy race car kids create a visual model of the Doppler Effect.

Step into the fantastic world of colors with a project that explores what shade you -- and your friends -- like best.

Take a closer look at your furry friend (or the furry friend of a neighbor -- with permission) to discover if communication exists between cats and humans.

Kids construct a single fixed pulley system to learn how pulleys can make work easier in this cool physics and engineering science fair project idea.

Chemistry is a blast with this backyard bomb made from a sandwich bag. All you need are ingredients from the pantry to create a satisfying, and safe, explosion.

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 balloon-powered car project is a great way for your kid to learn about energy and how it can be used efficiently.

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.

Is it possible to trick the forces of nature that make your bubbles round to create a square bubble?

Transform your uncomfortable wooden shoes into charming mini planters!

This science fair project idea demonstrates how air resistance contributes to denser objects falling faster than less dense objects.

Test your friends to find out if you can replicate the placebo effect's incredible results.

This science fair project idea determines if crystals will absorb food dye and if colors will mix by the process of diffusion.

Take this "paper plate snack test" with your child for a hands-on lesson in making healthier choices to teach your child about what's in his food.

Children will learn all about cause and effect as they experiment with potion-making in this Halloween themed activity.

How do organic materials become soil? This science experiment measures what materials biodegrade.

Is your little scientist up for a rocky challenge? Let them make their own geode rocks using eggs and epsom salts!

It's rhyme time! With this science fair project idea, your child will find out which words can be considered easy rhyming words, and why.

Beetles come in many shapes and colors. Here's how your second grade child can create his own beetles to paint and play with!

Take advantage of the spring and summer sun in this arts and crafts activity that has your learner creating pretty flower prints.

Create a self-portrait from natural materials in this collage craft activity!