This site has lots of great science gadgets you can make at home, including a spectroscope (which allows us to split light into the colors it is composed of) made out of a small box, some razor blades, a paper towel tube and dark tape. Here’s the result for fluorescent light:
This could be really fun to use with all different light sources in the house!
There are lots of other nifties to make too. Be sure to click on the list on the left (which is the experiments) rather than the right (which are kits to buy and could be helpful too!). The magnetorheological liquids sound pretty cool too!