This study investigated the effects of teaching the principles of behavior modification to students for use in the classroom. This intervention procedure involved four male high school students and their first-year psychology teacher. The students were instructed in behavior modification principles by two guidance counselors during group sessions. During the baseline period of the study, both the students and their classroom teacher rated each other on five selected problems behaviors. During the intervention period, students reinforced the teacher for desirable behavior, specifically when she allowed the class to participate in any discussion. Data collected by the students and teachers from this period and the follow-up period indicate that: (1) students can effectively reduce undesirable teacher behavior; and (2) concomitant changes in the students' undesirable behaviors can be effected. Data tables present the changes in student and teacher target behaviors as well as a comparison of the students' semester psychology grades. (SDH)