Science fair project that examines how temperature affects density and how density in turn affects the behavior of helium gas.

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.

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

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

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.

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

Science fair project which uses coins flips to visually demonstrate the probability of an event and how to express it.

Is cleaning with lemon effective? Get ready to give this science project some elbow grease and find out if acidic lemons can be used as a cleaning agent.

This science fair project idea identifies trees using a dichotomous key.

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

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

This science fair project idea explores how much force is needed to move a lever at different distances from the fulcrum.

In this experiment, students will discover how heat and pressure turn clay into slate, phyllite, and finally schist.

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

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.

Most people assume that cold water freezes more quickly, but could that be false? Does hot water freeze faster than cold water? Let's find out!

Learn about the fruit fly life cycle in this experiment. Capture fruit flies to examine various stages of insect metamorphosis.

This is a quick, easy science fair project that conveys the idea of density to preschool and early elementary children.

This science fair project idea explores whether people have an innate feel for the passing of time from a few seconds to 20 minutes.

This science fair project idea determines if the temperature of rubber effects how high it bounces.

What's the difference between a microwave and an oven? Use mashed potatoes to explore which kitchen appliance does a better job at keeping food warm.

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

This science fair project idea explores whether a plastic slinky works as well as a metal slinky when walking it down the stairs.

Check out this cool science project idea to learn about rocks and explore the cycles of formation, breakdown, and reformation of rocks in the Earth's crust.

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

Experiment with buoyancy to learn how a submarine rises and sinks in this classic science experiment.

Science fair project that determines whether landscaping fabric impacts the ability of plants to receive water.

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.