In case you're not friends with a lot of moms on Facebook who like to share videos like this, if you put Skittles in warm water they'll make a rainbow. This is a video demonstration of that. It makes a great experiment to perform with kids, although it should only be performed under close supervision with any overweight children because they will eat all the Skittles then try to convince you to see if it also works with M&Ms and Runts.
Keep going for the video.
Thanks to Allyson S, who misses doing math with candy. Me too, it was the only math I was ever good at.