What's the best way to make DIY compost? Kids will learn about aerobic and anaerobic decomposition while learning to appreciate the value of composting.

In this free science fair project idea, we learn about surface tension and how it can support mass—in this case, a floating paper clip.

What is biodiversity? Kids will study different areas of their backyards to see which is the most diverse to learn about biodiversity and random sampling.

In this simple science project, learn about what causes dew and what affects dew formation with a drinking glass, ice, and a soda bottle.

Learn about magnifying glasses, concave lenses and inverted images by sending rays of light through a magnifying glass in this cool science fair project!

In this cool physics experiment, use double plane mirrors at various angles to learn about light reflection. Then, see if you can solve a puzzling problem!

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

In this project, build an insect model that shows how the head, thorax, and abdomen fit together! Learn insect anatomy by constructing a paper mache critter.

Learn about where colors come from and how light absorption works in this fun experiment! All you need is a flashlight, construction paper, and cellophane!

This is a fantastic and easy science experiment where kids will learn about elasticity by testing how high bouncy balls of different materials can bounce.

In this plastic wrap science fair project, you'll learn about polymer permeability and find out which plastic wrap keeps food from dehydrating best.

What are the effects of colored light on plant growth? Explore plant behavior in this cool botany science fair project and learn about phototropism!

Learn about the effect of artificial light on plant growth versus natural sunlight and delve into some biology and botany concepts in this science project.

Total alkalinity and pH personal care products are controlled to prevent skin irritation. Learn more about basic and acidic substances in this science project.

Kids learn how to manipulate additive and subtractive colors to send secret messages with red colored filters in this cool science fair project idea.

In this experiment, kids will see if pruning tomato plants makes them more fruitful and learn about the factors that contribute to a plant's fruit production.

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

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 do animals keep warm? In this experiment, find out whether fat insulation resists cold temperatures and learn how this works in the animal kingdom.

Learn the basic structure of a DNA strand, which is the double helix, how genes form together, and the resemblance DNA has to a twisted ladder. Create a model.

Here is a fun middle school science project on factors affecting solubility. Learn how dissolved solids can "crash out" to form crystals when conditions change.

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.

How does rust form? Kids will learn about the roles oxygen, water, and electrons play in rust chemistry in this cool science fair project idea.

What are buttress roots? In this fun science project, make a model of a rainforest tree and learn how they help trees survive in the tropical rainforest!

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.

Learn how to tell time by the sun with this cool science fair project idea that tracks how the accuracy of a sundial changes over time.

In this cool experiment, learn how to find specific gravity of minerals using liquids of different densities to see which substances and items sink and float.

How does the size of a vibrating surface affect the pitch of a drum? Learn about drum size and pitch with this easy science fair project idea.

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