We are huge fans of The Magic School Bus. We have the DVDs for the whole series plus almost all the books. So whenever we are looking for a fun Science lesson that is where we go for inspiration. My DVD collection came with a nifty little experiment idea book and that is where this lesson came from. It goes along with the "Make A Rainbow" episode.
Clear glass or bottle
Smaller empty container
2-3 Tbs of vegetable oil
Fill up the the glass/bottle three quarters of the way with water. In the smaller container add the oil then drop food color into it. We used a few different colors and ours got a little dark so I might just use one or use lighter shades. Next, mix the food coloring and the oil together just a little. After that you pour the oil/food coloring mixture into the glass/bottle of water. Finally just sit back and watch as the colors slowly release from the oil and rain down to the bottom of the water it is beautiful. When our was finished the kiddos wanted to keep stirring and playing to see what happened so that is shown on the two last pictures.