Education.com is a great resource for homeschoolers. One section that I have been taking advantage of lately is their vast amount of science fair projects. My daughter is a hands-on kind of kid and many of the concepts taught in her Apologia science book can be demonstrated with science projects I find on Education.com's website.
You don't have to be planning a science fair (although homeschoolers can get together to have one) to use these experiments. Simply search the subject your child is learning about and scroll through the available project until you find one that interests you.