Free science fair project idea that examines the differences between cats and dogs. Analyze objective qualities rather than subjective ones.

This science fair project investigates why the number of visible stars changes from place to place.

In this science fair project, apply the principles of leverage and force by building six simple machines designed to set weights in motion.

This science fair project idea is develops new or improved paper making techniques and encourages recycling.

Prove that the Earth is not flat. The objective of this science fair project is to measure the angle of the sun and calculate the circumference of the Earth.

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.

In this experiment you explore how tectonic plates move to create land and expand bodies of water.

Young scientists will investigate people's preferences for saltiness, and make some inferences about genetics and diet.

examine how passive solar heating works, measure temperature in a parked car on a sunny day. ways to use passive solar heating as an alternative, energy

This science fair project idea examines liquids of different densities.

In this classic Ivory soap experiment, kids learn what happens to different types of soap in the microwave, and why!

This science fair project on testing water hardness is a great introduction to practical chemistry. Test and learn the difference between hard and soft water.

Science fair project that determines whether cooling eggs helps them be peeled more easily. Compare the time it took to peel each egg.

This science fair project idea examines whether plants are still able to grow normally if they are turned upside-down.

The project determines which laundry detergent is best for cleaning clothes.

This science experiment tests if dog saliva can really help heal wounds.

What's the difference between a microwave and an oven? Use mashed potatoes to explore which kitchen appliance does a better job at keeping food warm.

For this science fair project, kids will learn how to make a lemon battery. They can conduct this classic experiment using readily available materials.

This project explores whether plants can live and grow when "watered" with juice, soda, or milk.

What's the chemistry behind dyeing Easter eggs? Will adding vinegar to dye help the eggshell absorb the color? This colorful science project has the answers!

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.

While your cells are much too small to see without a microscope, you can create the look of a cell in your very own home with just an egg and vinegar!

In this science project, learn about water transport in plants and make a beautiful dyed floral arrangement with cohesion, adhesion, and xylem tubes!

In this fun science fair project idea, kids will experiment with various methods in order to discover the fastest way to cool a soda.

This light bulb science project includes step-by-step instructions for testing the heat from different light bulbs.

In this free science fair project, build a star clock and learn how to tell time on a clear night by observing the big dipper!

Science fair project idea that examines different physical characteristics of a chosen animal. Make educated guesses about evolution based on animal's form.

Future engineers, unite! Discover how to keep a sandcastleâs bridge from falling into the moat.

This science fair project idea identifies the properties of soap bubbles and invents a new or improved bubble solution.

The science project fair idea explores the interaction between your nose, mouth, and brain when tasting a new food or drink.