Some ideas for good science projects include examining whether black light detects invisible stains and why insects are attracted to lamps. Another potential project explores what kind of automotive antifreeze is safest for the environment and why.
Another science project tests how safe microwave ovens are. Compare the growth of a plant placed in close proximity to a microwave compared to a plant further from the appliance but in the same light and temperature. Take notes and observations at various points during the research to keep a detailed account of the plants' health throughout the experiment.
Another option for a science project is to test how different fertilizers affect growing plants. Perform this test by using fertilizers with different amounts of nitrogen, phosphorus and potassium. Conduct the test on the same type and size of plant to ensure the comparison is as accurate as possible. Take note on changes in height, number of blooms, size of the leaves and root development.
Another project is to test whether or not algae grows in bottled water. Study unopened bottles in direct sunlight. Use different brands of water and take notes on what happens to each brand during each stage of the experiment.