This looks like the all time coolest craft/science activity/gift! Make your own colorful rainbow paper with just three materials! Easy physics demonstration, art project, and science activity for kids of all ages. The Science Kiddo
This is another good resource of science projects for young children. Parents and teachers can use these for centers, science time, or just for fun! FUN Science Projects for Kids - perfect cure for summer boredom (great for toddlers as well!