What would be a good 6th grade graduation song?

Please don't say Graduation By: Vitamin C it's on every other question asked for this. And no cuss words or sexual references! I'm tired of songs always referring to this type of stuff! It's going to be performed in front of the entire school for our talent show and the kindergartners are going to be watching! Also please make it songs that a Mezzo-soprano can sing, I seriously cannot sing ANY low notes! (: