7th Grade is the only grade where Age vs. Grade matters
The 2018 forum is the perfect forum for this topic. In 12 months 2018 parents won’t care but will instead be complaining about how unfair the NLC tryouts are.

8th Graders are invariably never U-13 eligible so they all play U-15
-Pretty much all 8th grade teams are U-15 teams
-An 8th grader who is U-13 eligible should still play U-15 to prep for HS

6th Graders(even “older” ones) are invariably always U-13 eligible so they all can play U-13
-Pretty much all 6th grade teams are U-13 teams
-A 6th grader who is U-11 eligible should still play U-13 to avoid playing with elementary school kids

7th graders fit into 1 of 4 buckets – the bucket your child fits into likely drives your opinion on this topic
-Too old for U-13 and really good – You are torn, you want your son to play with his classmates, but are tired of hearing you are playing down so you register him as an 8th grader or U-15 you want this topic to go away
-Too old for U-13 and still developing – Your boy needs to play with his classmates as he will be overwhelmed playing 8th grade completion you are pro grade based
-U-13 eligible and really good – You want the older boys playing with your son so that your son is challenged as much as possible you couldn't care less as long as the completion is good
-U-13 eligible and still developing – You are concerned about you son being overwhelmed so you want to dilute the 7th grade talent as much as possible by eliminating older 7th graders. You may view having older boys compete with your son as a safety concern you are pro age based