Life science projects deal with living organisms, including humans, animals and plants. One idea for a sixth grade life science project involves determining why and how caffeine affects our bodies. Allow a student to test fellow classmates by having them either eat chocolate or sip a caffeine drink such as soda, testing their heart rates before and after. Another life science project relates to animals and determines how the echolocation systems of bats and dolphins differ. Students can display a graph of the different sound waves and play a recording of the sounds that bats and dolphins make to communicate using echolocation.
Earth science studies the Earth's elements as well as outer space. One project idea for sixth graders is to test what makes ice melt the fastest. The students can test melting ice cubes in the sun, with heat and with salt, then observe how and why each one melts ice. Another earth science project involves testing what materials decompose the best in landfills. The students can observe different types of plastic bags buried in soil for a few months, checking for signs of decomposition. This project can provide an understanding of the impact refuse has on our environment and promote the use of biodegradable materials. Testing the best environments for plant growth and determining what causes acid rain are also excellent ideas for earth science projects.
Physical science deals with non-living matter and energy, as well as with physical properties. Using balls of different sizes, students can drop them at the same time from several distances for a project on gravity that tests whether heavier objects fall faster than light objects. Frying pans of different materials can be used to test how different metals conduct heat. Cups of different sizes filled with different items can be used to demonstrate how air makes sound. For a science fair project on how airplanes fly, students can build model paper airplanes for demonstration or can make comparisons between bird flight and airplane flight.
Food science fair projects typically deal with the chemistry of food and what happens to food in different environments. One idea involves determining which fruits rot faster and in what conditions. Another looks at which fruits ripen further off the vine. Students can also do experiments to determine how crystals form from sugar to make rock candy; how milk curdles; or how milk and bacteria create cheese. Suggest testing how foods turn into other foods by demonstrating how grapes become raisins or how cucumbers become pickles. Students interested in a food science project can create their own projects by going through items in their refrigerators and pantries at home to see whether they can find foods they have questions about.