This science project uses Mohsâ Hardness Test to show kids how to compare the hardness of different types of minerals.

In this popcorn experiment, students can explore how two things made out of the same material can have very different appearances and densities.

In this project, the fingerprints of family members are compared to determine if people from the same family have similar fingerprints.

In this cool science experiment, learn about magnetism and poles, and test magnet strength to find out if two magnets are twice as strong as one.

This project compares the strength of one, two, and three-ply toilet paper.

This homemade barometer allows your little scientist to contemplate and compare different air and weather conditions.

In this science fair project, students learn how pressure can make the minerals in a rock line up in the same direction and form bands and foliation.

Compare animal and plant fats and observe, and record, and draw conclusions about their similarities and differences.

Have your kid determine if a goldfish can be conditioned to expect food the same way Pavlov's dogs did with this fascinating science fair project.

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

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

Use chemical analysis to identify a variety of mystery powders that look the same but actually have very different properties.

Enjoy those warm spring and summer nights with your child while teaching some basic astronomy at the same time.

Unlike other seed sprouting projects, this one allows kids to compare five different sprouts (either 5 herbs or 5 flowers) by watching them grow in a glove.

In this activity, students will think about the form and function of household objects as they compare and contrast kitchen serving spoons of various sizes and designs.

How greasy are your potato chips? Students will use a reliable method to quantify greasiness and compare different brands in this great science fair project.

Milk is made of water and fat; but how can you separate the two? Find out in this color changing milk experiment.

In this experiment, your child will create two compost bins and see if he can determine what attracts fruit flies.

In this fun science fair project, make two different scale models of our solar system using Astronomical Units and planets' relative size!

Is it solid or liquid? Create oobleck and witness the amazingly weird oscillation between the two!

This classic children's game-connecting two cups with a string-demonstrates sound's ability to travel through air vs through a solid.

In this Halloween-themed activity, young learners will find out what happens when they mix two household items together to create a surprising chemical reaction.

This project explores whether nails, toothpicks, straws, or pen nibs are best for applying ink to paper.

Science fair project which compares the rate of temperature change and the maximum temperature as a result of the angle of light radiation.

In this experiment, the weight of aluminum cans will be compared.

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

This science fair project idea highlights decomposition rates by comparing how long it takes an item to decompose in a compost pile vs. a landfill.

In this project, different brands of microwave popcorn are tested and compared.

Introduce your fourth grader to the concepts of solstices by observing the length of her shadow on the shortest day of the year, compared to other solstices.

This project demonstrates the correspondence between the volume of water displaced by a submerged object and the volume of the object displacing it.