The present exploratory paper addresses school-aged children's assessments of treatment outcomes using drawing as a self-report measure with usefulness for assessment and therapy. The process of using drawing in therapy can provide information on how a particular child perceives and conceives his or her own world. Examples are presented of drawings by three children with oppositional defiant disorder aged 10-11 years who participated in group intervention aiming to reduce aggressive behaviour. All three were asked to draw themselves twice on the same day at the end of treatment: (1) a retrospective drawing of themselves as they had been at the beginning of intervention; and (2) a drawing of themselves as they were now, after intervention. Children then described what they had drawn, revealing the change they perceived. Drawing as a self-report measure added information regarding: the child's ability for self-awareness; the link between thoughts, emotions and behaviours; and the process of change.