Leadership is certainly not about ‘just shouting at people’. We are talking about that, yes, but I have previously mentioned reading a game and the need for intelligence. A bit of leading by example is no bad thing.
As the sergeant-major said, “Excuse me, young chap, but would you be so kind as to try just a little harder to come to attention alongside all the others?”
(Incidentally, the best collection of teachers I worked alongside was in a comprehensive school principally serving a trio of pit villages.)