In a recent article in The New Yorker, James Surowiecki makes the argument that high performance coaching for athletes and classical musicians has become the standard for these professions and posits that it should be for educators as well. His position is that coaching is the best way to assure that teachers know the right things to do and continue to do them.
Surowiecki, J. (Nov. 10, 2014) Better all the time. The New Yorker.