Your age is your age. Shouldn't matter what grade your in unless it's crazy like a 20 year highschooler. Heck I've seen 16 year old 8th graders as well as kids that were 16 in their Senior year, they should both be in 16u. Let the kids decide, and maybe parents would quit redshirting their kindergardeners in hopes of haveing the biggest, fastest, strongest, and not to mention oldest Kindergardener.