So my husband is a pretty hands-on dad. I love that about him. Th other day he was searching online for some fun activities to do with the kids and he came across Steve Spangler. He's kinda like Bill Nye but without plugging the whole nerd-theme quite so strongly. He has a lot of fun hands-on science projects that you can do with your kids at home using things that you have lying around the house. This is one of our favorites!
Color Changing Milk
Fill the plate up with milk and then drop some food coloring drops in.
Dip your cotton swab in the dish soap and then place that tip in the milk near/on a color...
Here's Steve's video on it in case my explanation didn't cut it for ya!
Here is the link to his website and an endless collection of fun experiments to try at home!