Healthy Futures is an age-appropriate program that targets change at different social ecological levels-individual, interpersonal, and organizational. The main component is a classroom-based relationship education curriculum, Nu-CULTURE, offered in 6th, 7th, and 8th grade for eight 50-minute sessions each year. A number of supplemental efforts aim to enhance the Nu-CULTURE program and create social supports: 1) virtual classrooms where participating youth are encouraged to visit age-appropriate youth websites; 2) daily interactive parental connection forms linked with Nu-CULTURE, a parent website, and workshops (True Connections); 3) a 10-week after-school program, Rhymin' it Write, encourages youth leadership; 4) a 6-week summer program, Code A, engages youth during out-of-school time after 8th grade.

Participants were followed for the duration of the three-year Healthy Futures program delivered in 6th, 7th, and 8th grades. The primary outcome was measured approximately two years (8th grade) after the baseline (6th grade) questionnaire.

Prevalence of participants who reported vaginal sex was measured by participant response [Yes/No] to the question: "For the purposes of this survey, by sex, we mean a male putting his penis into a female's vagina. Other ways of saying sex are "doing it" or going all the way". Have you ever had sex?"