Children and youth are often challenged to maintain well-being, positive behavior, and social participation. To identify evidence for occupational therapy interventions for children and youth with and at risk for mental health concerns. Articles published in English-language peer-reviewed journals between January 2010 and March 2017 identified through searches of MEDLINE, PsycINFO, CINAHL, ERIC, OTseeker, and Cochrane databases. : The methodology in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses was used to complete the review. Of 5,310 articles screened by title and abstract, 357 were retrieved for full-text review, and 62 met inclusion criteria. Articles describing interventions that were activity or occupation based were included. Conference proceedings, non-peer reviewed publications, dissertations, theses, and presentations were excluded. Of the 62 studies included in the review, 20 (32%) were Level I studies, 22 (36%) were Level II studies, and 20 (32%) were Level III studies. Articles were categorized by type: outdoor camps, video and computer games, productive occupations and life skills, meditation, animal-assisted interventions, creative arts, play, sports, and yoga. Moderate to strong evidence supports the use of yoga and sports. Moderate-strength evidence supports the use of play and creative arts. Evidence for the use of animal-assisted interventions, meditation, video and computer games, and productive occupations was of low strength. Substantial evidence exists to support the use of activity- and occupation-based interventions to address the mental health, behavioral, and social participation concerns of children and youth. Occupational therapy practitioners should match the desired outcome of therapy with the appropriate intervention to provide the best and most effective services to their clients. This review provides additional support for the use of activity- and occupation-based interventions (i.e., those that involve active participation) to improve the behavior, social participation, and mental health of children and youth.