This study evaluated The Grassroot Project, a middle school sexual health promotion program in Washington, DC that uses university-level athlete role models and sports-based games. Seven schools were allocated to immediate (n = 160) or delayed intervention (n = 166). Students were tested before and immediately after the intervention on attitudes and self-efficacy to avoid sexual risk, intentions to avoid or engage in sexual intercourse, HIV stigma, and endorsement of violent behaviors. There was no evidence of differences between groups; however, the intervention has promise in respect of key outcome domains. This research justifies future longitudinal evaluation to assess behavioral and biomedical outcomes.