2. Does the teacher's supervision levels influence the relation between class context and on-task behavior? Based on our review of literature, we expected that teachers may adapt their levels of supervision to class context and children's specific needs in order to enhance children's attention. These adaptations will influence the interaction between context and group as described in the first research question. To better understand the basis of this relation, we investigated whether (a) class context conditions have an impact on the amount of individual teacher supervision in children with and without ADHD and (b) irrespective of context, whether levels of teacher supervision are related to on-task behavior in both groups. We assumed that, in general, one-to-one teacher supervision will be more common in the individual and small group conditions compared to the whole class group condition and that these teacher practices may particularly affect students with ADHD. We also hypothesized that higher levels of teacher supervision will be associated with more on-task behavior, but this effect may be different in children with and without ADHD.