Teaching functions

Hi all! I teach third grade in Edmonds, Washington.
In Course E, fourth graders are shown what functions are. They learn that functions are similar to a repeated chorus; though we don’t say the word “chorus”, we look at the top of the paper to figure out what the chorus is, similar to functions. The word (chorus/function) shows and tells us that line will be repeated several times, in different parts of the song (or program).
I would probably use the same strategy of using a song to teach my third graders about functions. I think that the song idea can reach a lot of students, because they all attend music at least once a week. I would like to use a song they currently know (or are learning in music), to make it easier for all the students to understand functions. Having all the students know the song would make it easier, as they could focus lesson on the chorus and more on understanding what a function is.