This study uses a cluster-level randomized controlled design to evaluate the efficacy of Re:MIX in reducing the incidences of early sexual behavior, unprotected sex, oral sex, pregnancy, and STIs. Re:MIX is a comprehensive in-school health curriculum and teen pregnancy prevention program for adolescents covering a broad range of topics related to sexual health and youth development, including healthy relationships, communication, gender, consent, reproductive anatomy, contraception, sexual decision making, clinics, parenthood, and life planning. Re:MIX also aims to connect students and peer educators with community resources and service linkages. The Re:MIX curriculum teaches mixed-gender groups of students in grades 8 to 10 to delay sex and use protection if they have sex. A co-facilitation team of peer educators (who are young parents) will deliver the information with professional health educators using non-traditional approaches, such as game-based tools, technology, and storytelling. Youth receive roughly nine hours and 10 minutes of group sessions during the school day over one semester (55 minutes per week for 10 weeks). Participants will be 8th, 9th, and 10th graders attending three public charter schools in Travis County, Texas. Comparison classes will either receive an alternative program that focuses on health, nutrition, and fitness, or business as usual. This study is being conducted as a Rigorous Evaluation of New or Innovative Approaches to Prevent Teen Pregnancy funded by the U.S. Department of Health and Human Services' Office of Adolescent Health.