All you need are the words to the song written on different colored paper ( I used construction paper), and then a small strip of all those colors to put in some type of container (I used a manila envelope). Then you call up a child (personally, I like to look for kids who are being reverent and at least attempting to sing, and I like to alternate between boys and girls), who then comes up and picks a color out (without looking!). Whatever color is chosen, you then remove all those matching color strips from the board.
We used it to work on our Father’s Day song but it can obviously be used for any song. It’s a great way to really work on a song that the kids are having a hard time with, since you’re slowly taking away words a few at a time.