According to Parenting, some of the top 10 best science fair projects include an experiment examining which type of soda is most damaging to teeth, the relationship between taste and smell, creating a fabric that can conduct solar electricity and looking at the way worms help create compost. Other good science fair projects include looking at the relationship between cars and pollution, and separating out ink colors.
Science fair projects rated highly by Parenting also include finding the relationship between soda and the discoloration of tooth enamel, examining the evolutionary traits of earthworms, separating liquids out by density and experimenting to find the appropriate solution for removing tarnish from coins. Another common project for school science fairs is a project using a potato to create a battery or clock. Students can also look at how to create a solar oven using a pizza box. A model of the solar system is also a good science fair project appropriate for all ages.
More advanced students can create a more detailed model, including more concepts from astronomy, while younger students can focus on the colors and shapes of planets. Creating a pinhole camera for a science fair can help students understand how the camera works and how it was invented. Growing a crystal garden is also recommended science fair project.