In this paper, pupils' misconduct in the classroom is interpreted as a change from on-task to off-task behaviour. This change entails a switch from a current learning behaviour to an activity that is more attractive to the student but that is seen as a discipline problem by the teacher. Thus, academic and non-academic goals of pupils rival one another. Motivational conflict theory is used to elaborate on the premise that a discipline problem is a consequence of goal shift. The theory is used to model off-task behaviour as a failure to coordinate academic and non-academic goals, to ask new research questions, and to draw practical conclusions about educational interventions. The paper closes with suggestions about how to strengthen pupils' ability to coordinate goals and how teaching can fulfil the various needs pupils pursue.