Good science fair projects could fall under a number of categories, including environmental science, astronomy, chemistry, and cooking/food science. For example, you could look at how light intensity from stars changes with distance.
Maybe: A Baking soda Rocket Flower growth project Purifying water samples Examining which balloons last longest or examining which type of battery lasts longest Also, try doing something that...
An easy one is to find two pennies, one that is from before the 1970's and a newer one. Cut one edge with wire cutters about 1/16th of an inch into the center of both the pennies. Put both of them...
Business, try to run your own business, and be intrigued in it. ......... For example for kids its a lemonade stand... distribute the money with your different partners! Try to find a teacher...