[thecavemaster]

I think a combination of factors are at worK:
* Participation rates among girls seem to be lower than
for the boys in the upper grades, creating roster spots
for younger players.

* Girls develop a bit faster than boys, so an 8th grade
girl is at less of a physical maturity disadvantage
than an 8th grade boy going against upper graders.

* Cheerleading is a HUGE competition for the athletes in
smaller schools, keeping numbers at levels where younger
players have to fill out the rosters.