This study examines the efficacy of an intervention designed to improve the classroom behavior of children identified with Attention-Deficit/Hyperactivity Disorder (ADHD). The intervention entailed training a class of third-grade students, including four students diagnosed with ADHD, to use self-management and peer-monitoring strategies embedded within a group contingency to decrease inappropriate verbalizations during class time. Findings indicated that the self-monitoring/group contingency intervention substantially decreased inappropriate talking-out behavior in all four subjects along with their matched controls. Implications as well as limitations within the study are discussed.