Science Fair Topic Ideas

Need some help coming up with a science fair project? Here are some tips.

Elementary school students’ science fair topic ideas usually fall into one of seven main categories. A brief description of each of those categories might help your child decide what type of project to choose for the science fair. 


kids' science fair project volcano
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Biology is the study of living things and how they grow. This includes both plants and animals. Among other things, project ideas can include experiments which look at how some factor affects growth or why certain environments are better for specific plants and/or animals.For elementary students, a project focused on plants is probably a safer bet than trying to do any experiments on animals. 


Chemistry is the study of substances. It looks at what happens when you combine them, creating compounds, and analyzes the reactions and materials involved. One project idea would be testing soil samples to see what compounds or minerals they contain. Knowing the periodic table of elements may prove useful when considering chemistry ideas. This is another area where parents may want to supervise younger children, and it's not a bad idea to invest in gloves and safety goggles if an experiment calls for any chemicals to be involved.

Earth Science

Earth science encompasses a great deal of things involving the Earth. It can include thing such weather and climate; volcanoes or other earthly phenomenon; fossils; rocks and marine life. A project focus might include an analysis of where certain types of weather occur and what the common factors are to encourage that weather phenomena, or something involving the impact of climate change on a given area. 


Electronics could also be thought of simply as electricity. These projects look at how electricity is conducted and can be controlled. This is also the category of project ideas that includes experiments with circuit boards and batteries. This is one to be approached with caution and will likely need adult supervision for students at the elementary school age. 


Astronomy is the study of the universe and all its components including stars, planets, moons, meteors and other celestial bodies. One astronomical project idea would be to build a sundial and to discover and explain why it works. Studying star charts and current astronomical conditions and planet positions could provide project ideas as well. 


Engineering involves designing, creating and studying the function of machines and their processes. An engineering project might involve designing a machine with an entirely new function using various simple machines in the process, such as a Rube Goldberg machine. 


Physicists study matter and energy. This may sound complicated until you know that this includes light, sound, magnetics and motion. If you’ve ever seen the egg in a bottle experiment, you’ve seen a physics science project in action. Physics concepts may seem a little advanced for younger students, but if they're into explaining how things work, there is likely an idea they can test for their project.