One comment on joes87 response regarding playing up/down, etc., and something I wish I had thought of earlier in the process.
I have a young 2016 who tried out for a team last year and made the top team for his age group in that organization. We were new and didn't know anyone,so didn't really know what grade the kids were in. Ends up that my son was one of only a few that were a 2016 on the team, as most were 2017's. Issue is that he has been playng mainly against kids a grade below his, as opposed to playing against kids that will enter college the same year as he does. The team iteself has been pretty successful in the PG circuit, so that has helped a bit with colleges, but I still think, had I been more aware, I would've spoken to the organization to get him to play with his class as opposed to his age.
Very good point Just-A-Dad, my son is entering 8th grade so we are leaning towards 14u just because that is what his grade mostly plays.