Learn how to make a ping pong ball anemometerâa device used to measure wind speedâin this free science fair project idea.

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.

Check out this fun and easy science fair project idea on germination of a seed and learn to identify exterior and interior parts of a bean seed.

Kids learn about potential energy, and mechanical energy, and how to make power from water with one of our favorite renewable energy projects for kids.

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.

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.

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.

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

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 windmill model science project, you will build a windmill to learn about wheel-and-axle machines and how these simple machines are used to do work.

What is the hydrologic cycle and how does it work? Check out this fun and easy science project where you will model and learn about Earth's water cycle!

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.

In this experiment, young ecologists will learn about a type of edge effect: how trees and plants at the edge of a forest can act as a weed filter.

In this project, all you need is a protractor to learn how to use the altitude of Polaris to find latitude on Earth. Polaris is also known as the North Star.

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.

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.

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.

This science fair project idea builds models of various types of bridges and then determines which bridge design is the strongest.

Find out whether a longer airplane will fly farther or a wider paper airplane.

In this experiment you observe and determine how well your cat uses his whiskers to navigate through a maze.

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

This science fair project idea develops an understanding through experimentation of which shapes are the most structurally strong.

Science fair project that determines whether tapping a pomegranate with a spoon helps it release its seeds.

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

Science fair project that determines whether lettuce that is harvested gradually yields more produce than lettuce that is harvested all at once.

Throughout history, people have used song as a teaching and memory tool. This project explores whether song improves a person's ability to retain information.

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