Interesting question, what does any coach at the high school level do to ensure the kids at the lower level are being coached properly? This topic started about which coaches are good in-game coaches and game planners, and it has been switched to developing talent years in advance.  Seems like a new topic altogether. 

In my observations, trusting middle school and junior high coaches is the best formula.  Stay involved, but don't do their job for them is the best method.