Seating arrangements in which children sat in rows and around tables were compared experimentally in three classes in a special school for behaviourally troublesome children with moderate learning difficulties. Children were observed daily in four two week phases: seated around tables, then in rows, again around tables, and finally again in rows. Percentage on-task behaviour was recorded along with rate of pupil disruption and rates of teacher approval and disapproval. In all three classes on-task behaviour doubled from around 35% to 70% as the conditions changed from tables to rows. Moreover, rate of disruption was three times higher in tables conditions. Teacher behaviour was also affected; positive comments increasing during rows whilst negative comments decreased. It is argued that these studies support the results of previous studies regarding the importance of ecological variables, such as seating, on classroom behaviour.