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 teaches about mold. Students will test different foods to see which grow mold the fastest.

This experiment has students record rat behavior to learn about the benefits of rats and research rat myths throughout history.

How can we describe the relationship of magnetic field strength vs. distance? Kids will find out with this free science fair project idea.

Are you ready to be a detective for science? Then get out your magnifying glass and start studying fingerprints!

In this free science fair project idea, we learn about surface tension and how it can support mass—in this case, a floating paper clip.

For this science fair project, kids will learn how to make a lemon battery. They can conduct this classic experiment using readily available materials.

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

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

These science fair experiments demonstrate the chemistry of rust and the oxidation process.

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.

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

Can a horse lead itself to the carrot? Train your horse with carrots and boxes and test horse memory in this fun zoology science fair project.

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.

Learn about this simple machine and make a pulley of your own to use for fun science trials.

Science fair project idea that examines different physical characteristics of a chosen animal. Make educated guesses about evolution based on animal's form.

This project determines what category of person is most likely to be ticklish.

Kids will learn how to show the direction of magnetic field lines and create a permanent model using iron filings in this great science fair project idea.

This experiment challenges students to forecast the weather based on the surrounding areas' weather.

This science project lets students explore the number of spots on a ladybird and how to treat ladybugs with respect.

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.

Science fair project that examines condensation and the conditions needed in order for dew to form.

This science experiment tests whether warm or cold water works best in making cut flowers last longer.

In this cool engineering science fair project, kids learn how to build Hero's engine: an enlightening example of Newton's third law.

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

This science fair project teaches students the differences between fruits and vegetables.

Find out whether soil amendments can improve soil conditions and help you grow a bigger beanstalk in this ecology experiment!

Science fair project that develops latent fingerprints on a non-porous objects by converting superglue from a solid state to a gaseous state.

Is it a square or a circle? See if you can trick your friends with this zany science project!

What's the science behind those out-of-sight roots? Find out if you can trick roots into growing in different directions.