Check out this fun and easy 4th grade science fair project idea that tests how gravity induces positive and negative geotropism (gravitropism) in bean plants.

In this activity, your child will be challenged to use simple materials to create a catapult for a small, lightweight toy.

Learn about magnifying glasses, concave lenses and inverted images by sending rays of light through a magnifying glass in this cool science fair project!

In this fun design challenge, your child will get creative with making structures out of toothpicks and gumdrop candies.

In this exciting and empowering challenge, your child will construct a bridge using marshmallows and toothpicks!

Magnets vary in strength. Have your young scientist figure out which kind of magnet is the strongest when you have him conduct this attractive experiment.

In this activity, your child will be asked to create a boat that can successfully float while holding 25 pennies.

In this experiment, students will create their own version of coquina, a sedimentary rock thatâs formed by seashells and sand, cemented by seawater minerals.

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

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

In this science fair project, we'll use a liquid crystal thermometer to find out whether exercising makes a difference in people's temperature.

In this science fair project, students create their own miniature salt flats at home.

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

This science fair project idea researches the different layers of the atmosphere and creates a visual representation of the atmospheric layers.

This science fair project idea investigates which objects float and sink in honey, water, and oil.

In this science fair project, students make their own rain gauge to measure rainfall.

This science fair project idea determines what household items are good conductors of electricity.

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

This science fair project creates a visual model of whatâs happening to sound waves as a car approaches and then leaves.

This science fair project idea determines what household items are good conductors of electricity.

What is persistence of vision? With this hands-on science fair project idea, students will demonstrate this cool and dramatic phenomenon in their own classroom.

In this outdoor science activity you'll find tips on how to create a nature journal by choosing a native plant or animal and tracking that species.

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

This science project teaches young students about germs, bacteria, and the importance of washing their hands. Students will test what is the best way to wash.

This science experiment tests why guacamole goes brown and if leaving the pit in will stop guacamole from turning brown.

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

Is it amplitude? Weight? Length of string? Kids will discover what factors changing the period of a pendulum depends on in this fun and easy physics experiment.

The goal of this fun science fair project idea is to microwave candy and investigate: do some colors of M&Ms melt faster than others?

This science fair project teaches students about wilting and browning of salad greens.