Learn how to make a weathervane with this fun and simple meteorology project for fourth graders.

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

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

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

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

This activity provides a solution to all those leaves on your doorstep, while also giving your child a fun science lesson.

Learn about lateral earthquake motion and its effect on high rise buildings in this simple 4th grade earth science experiment.

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

Kids learn how to prevent erosion by growing grass. They'll test soil with grass against raw soil in this revealing science fair project idea for 4th grade.

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

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 idea examines whether boys and girls differ in reflexes.

Plants and light seem to be good buddies, but how far does the friendship really go?

Construct and experiment with a periscope using reflected light rays to gather an image.

This science fair project idea examines whether the colors of the spectrum respond differently in the thermal aspect when radiated by the sun.

In this fun science fair project, make two different scale models of our solar system using Astronomical Units and planets' relative size!

Saturn is the ringed planet in our solar system, a gas giant with rings made of ice and dust. Let's make a cool scale model with an old CD and some glitter!

In this science fair project, you'll make a "ghost" appear in a test tube, and learn about what happens when hot water and cold water interact.

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

Try hammering some plants with your kids to teach them a valuable lesson in flower science while making beautiful artwork in the process!

Science fair project examining barometric pressure, and how it can be used to predict the weather. How does atmospheric pressures relate to weather conditions?

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

Can a toy car determine the strength of a magnet? In this cool magnet science fair project, young scientists will learn how to measure the strength of a magnet.

Want to see a great example of Newton's first law? Kids will learn about basic physics with this fun, ballistic experiment.

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.

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.

How does distance affect the spreading of light? Kids see diffraction and the inverse square law of light in action with this great science fair project idea.

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

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.

4th graders construct an ocean food web to learn about consumers and trophic levels, food webs, and food chains in this cool ecology science fair project.