My 15 yo son loved the autonomy of going to the Cafe promenade and having pizza and soda, they have wii tournaments, there's and arcade. They also get groups together to see the shows and did a Windjammer dinner.
They also have games of dodge ball and mini golf.
On our last crusie he got to be friends with another boy who he's still in touch with!
As boys will do, they hooked up with two girls and on formal night they went around to all the photographers and had pictures done! I never would have thought to do that and they came out amazing. ( and I'm a cheapskate when it comes to pictures).
I assure you he won't be bored.