In any school classroom, someone is going to be in control. It helps if it is the teacher. Should this not be the case, however, it will be school bullies and loud-mouths who run the show. Teaching quality and pupils’ learning will, of course, suffer and so will the teacher’s sanity. As teaching unions are fond of reminding us, 40 per cent or more of new teachers leave the profession within five years. How to keep control should be the first lesson of any teacher-training course. All too often, it is learnt only after new recruits start their first job. By that time it is, for many, too late.