Purpose: We evaluated the impact of a positive youth development program on adolescent pregnancy, sexual behavior, risky sex, and intentions in nonmetropolitan Florida high schools. Methods: Between 2012 and 2014, the Teen Outreach Program (TOP) was compared to standard school curriculum content using a cluster randomized controlled trial design with 7,976 youth in two cohorts. The majority of youth were 14 years old and in the ninth grade at baseline. Treatment group youth received TOP in health-related classes. After using multiple imputation to account for missing data, we analyzed baseline and follow-up survey data using generalized linear mixed-effects models with logit link function. Results: In the cohort 1 sample, compared to the control condition, males and females receiving TOP showed lower odds of engaging in recent sex (odds ratio [OR],.71; 95% confidence interval [CI]: .58-.86) compared to control males and females. Cohort 1 treatment females who did engage in recent sex were less likely to have risky sex (OR, .54; 95% CI: .32-.89). There were fewer significant findings in cohort 2, though TOP females and combined gender had lower odds of risky sex intentions (OR, .53; 95% CI: .33-.84 and OR, .65; 95% CI: .44-.96, respectively). Overall, cohort 1 females in the TOP condition were the group most likely to benefit from TOP. Conclusions: Consistent with previous research, TOP was more effective regarding sexual health outcomes among female versus male youth; this was especially true for the outcome of risky sex. However, results were not consistent across cohorts, prompting questions for future research. (C) 2016 Society for Adolescent Health and Medicine. All rights reserved.