CHS is legit this year and the entire MIAA is really good this spring. St. Pauls has a great goalie and an attack that could compete at the DII level right now.
I hesitate to address this because the chatter is actually about the great game of lacrosse but...
A lot of private schools use a pre-first curriculum which is why many of the kids are a year older than public school kids. Holdbacks are not a prevalent as you may think. I used to be the king hater of holdbacks until I got to know the system a little better. This is especially true for kids who transfer in 8th or 9th grade from public to private. In order to compete they do a "do over" year. No harm, no foul. If it helps the kid, who cares. Since MIAA schools operate under the same rules I see no issue with kids being older. Just understand that you cannot compare public to private kids.
As I have mentioned on this board before, you can find many older kids on city public school rosters because of inconsistent attendance and residency histories. Many freshman enter city schools at 15 or 16 years old. A county freshman is different than a city freshman.