No that is not how that works. A grade based team is based on the year the kid will graduate high school. Its set up so when a scout is watching a game he will know what year the kids on that team will leave high school. Like it or not with a grad based system those are the kids from your sons class no matter if they are 1 or even 2 years older then him. Its lacrosse people the bigger older kids can not tackle your sons so everyone will live just fine.