This science project has students study a group of volunteer liars actively lying to study the behavior of a lie. Students see if they can figure out the truth.

This science fair project idea examines liquids of different densities.

This science project allows students to study the psychology of happiness.

The objective of this science fair project is to study the photosynthesis process and demonstrate the important role that leaves play in the process.

This study evaluates if electronic devices commonly found in most households emit radiation, and if they do, how much?

Do you have your isopods straight? Learn about sow bug and pill bug behavior by building a terrarium to study them in!

The purpose of this science fair project is to study the properties of sugar and examine individual preferences for sugar and other sweeteners.

The purpose of this study is to determine if people can tell the difference between organic and conventional food from looking at, smelling and tasting it.

What is biodiversity? Kids will study different areas of their backyards to see which is the most diverse to learn about biodiversity and random sampling.

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

Collect meteorite dust with a magnet in your very own backyard! The objective of this science fair project is to gather meteorite dust to study outer space.

This science project challenges students to study deer behavior in their natural habitat- the feeding patterns, social behaviors, male to female ratio, etc.

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

This science fair project compares the allelopathic affects of juglone, a chemical agent produced by the Black Walnut tree, on two plants.

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

Check out this fun and easy 4th grade science fair project idea that tests how gravity induces positive and negative geotropism (gravitropism) in bean plants.

This science fair project teaches you about what makes persimmons so tart and how astringency can be removed by studying the effect of tannins on fruit.

This science fair project idea studies which brand of wintergreen candy produces the most sparks in the dark.

This science fair project idea studies which kind of rock (sedimentary, igneous, or metamorphic) is most damaged by frozen water.

Do you love to make Jell-O? Find out in this science fair project idea if it is possible to make Jell-O with just warm water.

The project investigates the affect music has on plant growth while experimenting with rock, classical and no music.

Ant behavior is closely related to light intensity. This free science fair project idea examines how fast ants dig when they are exposed to to light and dark.

Is there a relationship between caffeine and heart rate? Students will determine the effect of caffeine on heart rate in this fun science fair project.

This science project teaches students the relationship between compost and plant growth. Students conduct an experiment with different types of compost.

How do organic materials become soil? This science experiment measures what materials biodegrade.

The objective of this science fair project is to set up a compost bin to convert food scraps and organic waste.

Observe corn seed germination to learn about dicots and monocots and how plants grow from seeds to seedlings to full-grown plants!

Check out this science project idea to compare organic produce to non-organic produce and how preservatives in food extend the shelf life of goods.

Check out this cool science fair project idea that models the behavior of the cold desert plants: xerophytes and halophytes.