> If you haven't played school sports or don't have kids who play sports, a coach can often wield more influence over a kid than parents can.

I heard a (possibly apocryphal) story. One of Tony Dungy's kids was playing high school football, and was just grabbing a slice of toast for breakfast. Tony tells him "you need a bigger meal with protein before practice."

A week later he sees his son getting up early to make a big breakfast, and comments on it. His son says "yeah, coach told me I need to eat more"