We used a multiple baseline across subjects design to investigate the effects of self-monitoring on the on-task behavior and spelling accuracy of three fifth-grade students diagnosed with attention deficit hyperactivity disorder (ADHD) during an independent spelling practice period in the general education environment. We also compared their on-task levels to that of peers without disabilities in the same classroom context before and after the self-monitoring intervention. Our results showed that time on-task and spelling accuracy increased for the students diagnosed with ADHD during independent spelling practice after the teacher taught them how to self-monitor. These same students' on-task behavior also increased to levels comparable to that of their peers. Suggestions for educators interested in teaching their students self-monitoring strategies are included following a discussion of the results of the analysis.