When my son was 15 he was a huge baseball fan and played on several leagues. His bedroom was hand striped like a Yankees uniform and I made a quilt of a baseball field. The pictures didn't come out well and the quilt has seen much better days, but he loved it!
I would also think about doing geometric designs or maybe just a two color quilt. Something to match his favorite outfit or his room. The ideas are endless.
Good luck. Can't wait to see what you come up with.