Is it solid or liquid? Create oobleck and witness the amazingly weird oscillation between the two!

In this sound experiment children listen for differences as they tap on a bag of air, a bag of water, and a wooden block held up to their ears.

Your child helps the environment while saving your family money in this fun and rewarding "Gas Guzzlers" competition.

Science fair project that examines the different types of precipitation, evaluates the density of snow and calculates the ratio of snow-to-liquid.

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

Get your hands on a concoction that breaks the rules about what's a solid and what's a liquid.

How does dishwashing liquid work? Kids discover the chemical mechanism behind cleansing power in this easy science fair project idea.

What's a liquid? What's a solid? What better way to experiment than by turning a childhood favorite, ice cream, into a homemade science lesson!

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.

Would your child like to learn about a hidden world? All she needs to do is open her box of markers!

Science fair project that examines how yeast grows, and which conditions allow for optimal growth. What types of nutrients does yeast prefer?

The objective of this science fair project idea is to examine light refraction as it passes through liquid crystals.

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

Try this experiment to give your curious kid a more "solid" understanding of how temperature affects the states of matter.

Teach children how to upcycle dried-out markers with this homemade paint-making activity!

The objective of this science fair project idea is to determine if sound travels best through the air, water or a solid.

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

Determine which kind of rock (igneous, sedimentary, metamorphic) has the greatest reservoir capacity, which is the ability to hold the most oil and natural gas.

This science fair project idea explores whether boiling and freezing water will have an effect on how much it weighs.

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?

This science fair project idea examines whether adding gelatin causes a solid to have a higher melting point and/or melt slower.

This experiment uses a yeast solution, liquid detergent, and hydrogen peroxide to produce an exciting reaction like no other!

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

Put your second grade scientist to work this Fourth of July with our colorful "liquid fireworks" project!

Check out this fun science fair project to make a vinegar and baking soda balloon and demonstrate how gas is created as a result of the chemical reaction.

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.

In this activity, your child will make her own "quicksand" to better understand how a substance can be both fluid and solid at the same time.

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

Invite your fifth grader to test the different rates of liquid absorption in synthetic and cotton materials, such as nylon and cotton.

In this science experiment, observe convection currents forming and learn about how heat energy moves in liquids from hot to cooler areas through convection.