Youth with attention problems are at increased risk for school disengagement (Booster et al., JAD 16:179-189, 2012; DuPaul & Langberg, in: Barkley (ed), Attention-deficit/hyperactivity disorder: A handbook for diagnosis and treatment, Guilford, New York, 2014), which portends risk for poor outcomes (Bond et al., JAH 40:357.e9-357, 2007; Carter et al., JA 30:51-62, 2007; Fredricks et al., RER 74:59-109, 2004). Interventions that target school engagement may benefit from peer delivery because peers are widely available in schools and potentially more credible than adults. In this study, a peer-supported school-based school engagement intervention for middle school students with attention problems, Together Engaging and Achieving Meaningfully (TEAM) was developed with educators and students. In initial development (Study One), community development team meetings with partners (N = 9 school staff and students) were conducted. Thematic analysis was used to identify themes used to refine TEAM. In Study Two, a single-case pilot with one student with attention problems and one peer coach was conducted. Measures of fidelity, attendance, acceptability, and satisfaction were collected. Results were used to refine TEAM. Then in pilot implementation (Study Three), a non-randomized pilot was conducted with 10 fifth- through seventh-grade students with attention problems (n = 6 in the intervention group) and six eighth-grade coaches. Measures of fidelity, attendance, acceptability, satisfaction, and clinician-required time for implementation were collected. Cohen's d mean difference effect sizes were calculated between and within groups over implementation. Feedback from partners highlighted barriers and aspects that were acceptable and feasible. Results from implementation suggested high attendance, high coach fidelity with revised implementation support, and low clinician-required time. Lessons learned and avenues for future development and research are discussed.