The present study focuses on two major questions. First, how often are potentially reinforcing behaviors emitted by teachers in naturally occurring classrooms? Second, what is the relationship between the display of potentially reinforcing behaviors by the teacher and the task-orientation of randomly selected students in the classrooms. Students and teachers in four middle-school classrooms were observed for five class periods over a three-week period. One observer watched the teachers' facial, physical and verbal behaviors every 10 seconds and coded the behaviors as being positive, negative, or neutral. The other observer watched each student in the room for 10 seconds and coded the behavior as being task-oriented or non-task-oriented. The results indicated that an overwhelming percentage of teacher behaviors were "neutral" in nature. In addition, there was no relationship between teachers' use of potentially reinforcing behaviors and student task-oriented behavior. Implications for classroom instruction are presented. (Author)