Is cleaning with lemon effective? Get ready to give this science project some elbow grease and find out if acidic lemons can be used as a cleaning agent.

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.

This science fair project idea produces sounds by creating vibrations using different objects.

Sink or swim? Calculate the density of various fruits and vegetables using water and a kitchen scale.

Science fair project examining barometric pressure, and how it can be used to predict the weather. How does atmospheric pressures relate to weather conditions?

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.

This science project challenges students to learn about and classify weeds and discover new practical uses for weeds.

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

Science fair project in which you will examine how crystals are formed by creating your own crystal using charcoal briquettes, salt, and ammonia.

This science fair project idea determines if family members can recognize one another using only the sense of smell.

The objective of this science fair project is to examine the basic principles of air pressure using simple materials like a balloon, straw and string.

This project determines the age of a tree using a growth factor chart instead of cutting the tree down to count the rings in its base.

Experiment about connection of senses of taste and smell. Using blindfold and noseplugs, administer blind taste test. Analyze results and organize data.

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.

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.

Demonstrate how you can make your own compass using a magnetized needle. It also allows you to compare magnetic north and geographic north.

What causes the seasons to change? Kids find out by modeling the earth's tilt using a globe, flashlight and graph paper in this cool science fair project idea.

Study the life cycle of the common blowfly as it relates to forensic investigation. Record the first time you see flies, maggots, and eggs.

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.

Along with being an interesting science activity, dehydrated strawberries are also tasty â and healthy!

Science fair project which measures the shadow cast by a meter stick at various times in order to predict the circumference of the earth.

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.

This science fair project idea compares biodiversity between drops of water.

Wind is an important source of renewable, green energy. The purpose of this science fair project is to build and operate a windmill generator.

In this fun activity, your child will create their very own solar oven to bake s'mores!

In this activity your child will create their very own marble maze!

Science fair project which determines whether people are more likely to follow rules if they are easy to understand.

This science fair project idea examines the reason boats are shaped and engineered.

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