To explore the benefits of a brief autism education intervention on peer engagement and inclusion of autistic children at day camps. A convergent, parallel, two-arm (intervention/no intervention), non-randomized, mixed-methods design was used. The individualized, peer-directed, 5--10 min intervention included four components: (1) diagnostic label, (2) description and purpose of unique behaviors, (3) favorite activities and interests, and (4) strategies to engage. A timed-interval behavior-coding system was used to evaluate engagement between each autistic camper and their peers based on videos taken at camp (days 1, 2, 5). Interviews with campers and camp staff explored why changes in targeted outcomes may have occurred. Percent intervals in which the autistic campers were jointly engaged with peers improved in the intervention group (n = 10) and did not change in the control group (n = 5). A large between group intervention effect occurred by day 5 (Z = - 1.942, [eta-squared] = 0.29). Interviews (5 autistic campers, 34 peers, 18 staff) done on the last day of camp in the intervention group garnered three themes: (1) "Changed behavioral attribution," (2) "Knowledge facilitates understanding and engagement," and (3) "(Mis)perceptions of increased inclusion." A brief educational intervention that includes individualized explanatory information and strengths-based strategies might improve peers' understanding of and social engagement with autistic children in community programs such as camps.