Wow, in the metropolitan pga junior
8-11 year old foward tees and nine holes only
12-14 year old middle tees
15-18 year old back tees.
The cutoff for age is july 29th. 10 years old seems early to move to the middle tees. You want to get juniors to score well so they know they can do it.

Regarding preivous idiotic posts I make on this chain, what I was thinking of was the ratio of ball speed to club head speed. I think they refer to this as the smash factor. You want to get this as close to 2 as possible. a ratio of 1.5-1.6 is excellent. Obviously you will need a machine to measure all this.