In this cool science experiment, learn about magnetism and poles, and test magnet strength to find out if two magnets are twice as strong as one.

This project compares the strength of one, two, and three-ply toilet paper.

In this science fair project, young children discover what happens when two fluids that have different densities get together.

In this popcorn experiment, students can explore how two things made out of the same material can have very different appearances and densities.

This science fair project compares the allelopathic affects of juglone, a chemical agent produced by the Black Walnut tree, on two plants.

In this experiment, your child will create two compost bins and see if he can determine what attracts fruit flies.

Milk is made of water and fat; but how can you separate the two? Find out in this color changing milk experiment.

This classic children's game-connecting two cups with a string-demonstrates sound's ability to travel through air vs through a solid.

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

Learn how to make an anemometer with step-by-step instructions in this cool science fair project idea for 4th grade.

Kids explore how a single movable pulley can confer a mechanical advantage over a fixed pulley in this cool engineering science fair project for 2nd grade.

What do ants eat? Kids find out by observing a colony of ants in this cool zoology science fair project for 4th grade.

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.

Check out this fun science fair project idea for 1st grade: a solar eclipse model that demonstrates total, partial, and annular solar eclipses.

What heats up fasterâwater or soil? 5th grade students test the specific heat of water against the specific heat of sand in this great science fair project.

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.

Kids will learn how to make a steam powered rocket boat, also called a putt putt boat or a pop pop boat, in this great science fair project for 4th graders.

This science fair project examines which fruits and/or vegetables will ripen prematurely when placed with ripe apples.

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.

What animals are most popular? This project affords practice in data-collection, record-keeping and data-analysis through the investigation of this question.

Wonder why bugs always fly around your lights at night? This experiment determines whether insects are attracted to the heat or the light.

Demonstrate how static electricity can cause an object to move. It also examines just how an object affected by static electricity will move.

The objective of this science fair project is to analyze the effects of salinity and temperature on water.

This project demonstrates the correspondence between the volume of water displaced by a submerged object and the volume of the object displacing it.

The objective of this science fair project is to set up a compost bin to convert food scraps and organic waste.

Test whether plants can grow without sunlight and water.

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

Demonstrate how to tell the age of an egg without having to crack it open.

This science fair project idea provides evidence that air is everywhere and takes up space.

This science fair project looks one of the most important factors affecting seed germination: water. A fun and easy plant biology experiment for 3rd graders.