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.

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.

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.

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.

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.

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.

Science fair project about work and energy which uses a simple mathematical formula to predict how far a jar will roll down an incline.

This science project encourages students to investigate the Mozart Effect, the idea that classical music promotes learning.

This science project lets students explore the number of spots on a ladybird and how to treat ladybugs with respect.

Science fair project that examines condensation and the conditions needed in order for dew to form.

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

This science fair project idea explores which fruit molds the fastest.

Science fair project which simulates the global conveyor belts on a small scale, and observes the effects of wind, density and temperature on water movement.

Tree rings can tell the age of the tree but also information about the world. This science experiment uses tree stumps to discover new facts.

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

In this project students experiment with making music using only glasses of water.