Every Monday evening during the football season, Tony Franklin, the offensive coordinator for the Cal Bears, closes his office door, kicks back in his chair and hosts a conference call. On the other end of the line: 250 top high-school coaches from all over the country.

These sessions started as a way for aspiring coaches to seek advice from one of the most innovative offensive minds in football. Franklin’s Cal offense has already racked up 108 total points in just two games this season. But in recent years, a funny thing...