Kids will conduct a cool limewater carbon dioxide test that can be performed with common household materials to learn about the chemistry of this common gas.

This science project uses Mohsâ Hardness Test to show kids how to compare the hardness of different types of minerals.

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 are the effects of fertilizer on plant growth? What's the best fertilizer type (solid, liquid or powder)? Kids find out in this science fair project idea.

Kids get step-by-step instructions for how to make a rubber band car and explore the physics of potential energy with this fun engineering science fair project.

Does electricity move better through thick wires or thin ones? kids will conduct this classic electricity experiment for this science fair project.

Is it magic? No...it's the amazing, gravity-defying capillary action experiment! Kids will love this dramatic and enlightening science fair project.

Kids will love making sugar crystals in this sugar crystal science fair project which teaches important chemistry concepts like saturation and solubility.

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

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.

Kids will learn about the interaction of lactose and lactase in milk and discover why we describe enzymes as catalysts in this fun science fair project.

Create safe lightning for kids! They'll learn how to make lightning at home with this fun science fair project idea illustrating static charges and grounding.

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.

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.

How does a compass work? What's a magnetic field? Kids will build their own compass at home to find the answers in this great science fair project idea.

Kids build a desert food chain, desert food web, and desert food pyramid in this cool science fair project to learn about trophic levels and consumers.

How good are humans at sound localization? Kids can try this cool science fair project idea to see how good their friends are at judging sound direction.

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.

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

What do worms eat? Kids find out what kinds of rotting leaves and vegetables worms prefer in this cool compost science fair project.

In this free science fair project, learn how to separate salt from water using heat. A great science project for elementary school kids.

Kids will learn how to make a thermometer to to explore liquid density in this great science fair project. Which liquids are affected by temperature the most?

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.

It's not actually that hard to get energy from garbage! Kids learn how to make biogas in the form of methane with this cool and easy science fair project idea.

In this science fair project, kids observe the expansion of liquids when frozen and determine if some liquids expand more than others in the freezing process.

Build a 3d animal cell model with this cool science fair project, which helps kids visualize and understand the function of a cell's parts and organelles.

In this cool catalase and hydrogen peroxide experiment, kids put a potato in a jar of hydrogen peroxide to see how catalase acts as an enzyme.

What causes the seasons to change? Kids find out by modeling the earth's tilt using a globe, flashlight and graph paper in this cool science fair project idea.

Does putting soapy water on plants help or hinder plant growth? Kids learn about greywater and how it affects plant growth in this cool science fair project.

Do hand soaps and sanitizers prevent the growth of bread mold? If so, why? Kids will find out with this fun and informative science fair project idea.