When my kids were young and I was a stay-at-home parent, we did a lot of experiments. They loved exploring the world by making any kind of mixture, and sometimes I helped channel that by planning out a mixture that would actually react. It was sometimes messy, but always fun! I found this post on Babble that links 10 different science experiments to do. They're not all just for Halloween, like my favorite slime recipe from Our Best Bites, but the abundance of pumpkins makes them a lot eaiser.