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.

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.

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.

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 project, learn about animal vision and different kinds of eyes: ocelli, compound eyes, and camera eyes. Find out what a jellyfish or grasshopper sees!

With this cool floating rocks project, your child will get some hands-on experience with buoyancy and learn why certain rocks like pumice are able to float.

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.

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 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.

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!

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.

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.

Can a toy car determine the strength of a magnet? In this cool magnet science fair project, young scientists will learn how to measure the strength of a magnet.

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.

How does frost form? How fast does it form? Do this simple science project using a plastic glass, rock salt and some water to learn about deposition.

The moon doesn't produce its own light, so why can we see it shining in the sky? Learn about reflection and planetshine in this fun and easy science project!

Make a backbone model to explore human anatomy and life science.

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

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.