Teachers do not regard themselves as free agents in the classroom. They experience a number of constraints on their activity which influence their aims and ambitions, and, as Leacock (1969, p. 202) has observed:

Teachers cannot simply interact with the children in their classrooms according to their desires and personal style. Instead their behaviour often takes on characteristics beyond their immediate aims or intents. They must adapt their style, not only to the children but to the institution, to the principal's requirements, to the other teachers’ attitudes, and to the standards according to which they will be evaluated.