"Stress in adolescents is increasing (APA, 2014), and there is a need for adolescent-targeted programs to promote adaptive coping through the teaching of effective coping skills (Foret et al., 2012; Frydenberg & Lewis, 2000). Schools have been proposed as an appropriate site to implement such programs; however, existing programs are lengthy and require additional time and resources (Fridrici & Lohaus, 2009). The present study evaluates StressOFF Strategies (StressOFF; Shapiro & Heath, 2013), a single-session (45 min) adolescent-targeted, school-based stress management program that introduces cognitive behavioral and mindfulness based techniques. Participants were 227 Grade 9-11 students from 27 classes in seven secondary schools. Classes were randomly assigned to the treatment group (n = 89; 58% male, 42% female) or to an active control group (n = 138; 44% male, 57% female), which received a study skills based stress management program (Be PREPARED; Shapiro & Heath, 2015). At pre-program, participants completed a questionnaire of prior experiences with stress management as well as measures of perceived stress, test anxiety, and mindfulness. At immediate post-program, participants completed a program response questionnaire, which evaluated students' perceptions of amount learned, level of difficulty of program, overall program rating, recommendation to a friend, and understanding of strategies and willingness to use them. At one-month follow-up, the program response questionnaire was completed again along with measures of perceived stress, test anxiety, and mindfulness. Pre-program, participants in both conditions reported comparable findings of limited knowledge of stress and stress management, moderate interest in learning about stress and stress management, and they reported regular use of stress management strategies, such as distraction. One month following participation in the programs, students in the StressOFF and Be PREPARED groups reported decreased perceived stress, increased mindfulness, and decreased test anxiety levels. Although both StressOFF and Be PREPARED were found to be effective at improving mental health outcomes over time, students reported learning more from StressOFF and rated the program more favorably. Students provided comparable reports of program difficulty and recommendation to a friend for both StressOFF and Be PREPARED. Over time, however, in both groups, students' ratings of amount learned, level of difficulty of program, program evaluation, and friend recommendation all decreased. Immediately following the program, students in StressOFF and Be PREPARED reported high levels of understanding and moderate to high willingness to use strategies. However, like their program response, in both groups, students' understanding and willingness to use strategies generally decreased over time. Only their reports of willingness to use the Prioritize, Reading, and A good study space strategies from the Be PREPARED program were sustained at one-month follow-up. Comparable effectiveness of StressOFF and Be PREPARED suggests that a single-session stress management program can improve students' mental health outcomes over time. Specifically, students may benefit most from the components of psychoeducation and stigma reduction shared by both programs; however, there is indication that students prefer StressOFF and report learning more than students who participated in the Be PREPARED program. Interestingly, despite self-reported benefits in stress, test anxiety, and mindfulness over a one-month follow-up period, students in both groups reported decreased ratings of program and strategies over that time, suggesting a possible need for ongoing strategy and program reinforcement. Findings from the current dissertation provide encouraging support for the implementation of a single-session stress management program in the schools; although, to ensure maintenance of strategy use, ongoing follow-up is recommended." --