SUMMARY.A sample of 130 secondary school teachers was systematically observed teaching mixed classes varying in age from 11 to 16 years. The OPTIC schedule was employed to record teachers' rates of approving and disapproving responses and the amount of time pupils spent on-task. Although rates of approval were generally higher than disapproval rates, most of the approval was directed at academic pupil behaviours whereas most of the disapproval was for inappropriate social behaviour. Mean on-task behaviour of classes at 80 per cent was higher than that observed in a similar sample of primary classes.INTRODUCTION BEHAVIOURAL approaches to classroom management commonly advocate increasing teacher approval and decreasing disapproval (see, for example, Wheldall and Merrett, 1984), since it has frequently been demonstrated that contingent teacher approval can function as a powerful reinforcer of pupil behaviour. This is true not only for primary aged children but also for young people attending secondary schools (Wheldall and Austin, 1980;Merrett and Blundell, 1982; Wheldall and Merrett, 1987;Merrett and Wheldall, 1987a). Relatively little is known, however, about the ways in which approval and disapproval are normally employed in secondary school classrooms.The earliest study conducted specifically to determine natural rates of teacher approval and disapproval appears to be that of White (1975) in the United States. Under White's guidance 16 observational studies were carried out (employing the Teacher Approval and Disapproval Observation Record) with 104 teachers in classrooms from grades 1 to 12. The findings showed generally that, with the exception of those teaching grades 1 and 2, teachers gave more disapproving than approving comments to their pupils, with overall rates declining as pupils got older. The approval rate for instructional (academic) behaviour was higher in all grades than the rate of disapproval. With reference to managerial (social) behaviour, the rate of disapproval was very much higher than the rate of approval, which was described as "almost non-existent".Heller and White (1975) subsequently observed five teachers of mathematics and five teachers of social studies each teaching a higher ability and a lower ability class in grades 7 to 9 (i.e., lower secondary aged classes). Mean rates of disapproval were again found to exceed mean rates of teacher approval. Moreover, out of the total of 1,105 statements of approval and disapproval recorded, only one was found to be approving of social behaviour. Additionally, it was found that whereas teacher approval did not differ in rate between high and low ability classes, rates of disapproval were much higher in the lower ability classes.In New Zealand, Thomas et al. (1978) observed the classroom behaviour of 10 grade 7 teachers (i.e., classes of 11-to 13-year-old pupils) in the Mangere Guidance Unit, a clinical treatment facility. A time sampling instrument was used to record teacher behaviours and the on-task behaviour level of all 10 pupils. Results si...