Song for rehearsal

Hello all.

Recently I have been chosen to perform to represent my house in a school piano contest, after which I found out that the piece could only be around 3 minutes long. As I know that I'm definitely going against at least one person who's also grade 8, I need some good reccomendations for songs that are under 3 minutes or around 3 minutes that are still beautiful and might impress the judges. If you have any suggestions please tell me.