Behaviour management is acknowledged as a leading psychological method to reduce classroom conflict by applying "rational choice" techniques. But it falls short in schools where poor academic results are reproduced, as is illustrated in an analysis of misbehaviour in an Australian rural school. It is argued that explanations of behaviour management are over psychologised. That is, rather than being of assistance, the approach can generate out-of-reach and unworkable strategies, and place the staff in indecisive positions not open to rational choice explanations. Rather, in considering misbehaviour, it is argued that three factors need to be considered: how classroom interaction is ordered, the institutional effects of disengagement from learning, and a resulting struggle between a school's official order and the student expressive order. This paper illustrates how relations between these orders determine the social form a school operates from, and towards which changes should be directed. A social psychology is sketched around these points and considered according to Durkheim's criteria for social facts.