They were born after August 31st, 1999. That is US Lacrosse's definition for U14. If understanding this concept is really that difficult, I suggest that you invest in tutors for your son. US Lacrosse wants age based, not grade based play. Red-shirt Kindergarten, 8th grade I in Public School, Eighth grade II in Catholic school. 2016 becomes 2018. Don't wine about getting beaten by kids the same age or younger just because their parents follow NYS educational guidelines instead of making up their own.