Once the kid is in high school I don't really care how old he is - at that point - most kids - except for some late blooming freshmen will have hit puberty. I do have a problem with kids that should be in the 10th grade - who have hit puberty - playing against on age 7th and 8th grade kids in a youth lacrosse program. Its dangerous, its unfair and a return to grade based classification with an end of early recruiting would seriously curtail the need/desire of parents to have their kid repeat a grade.