In the United States, adolescents 15 to 24 years of age account for nearly half of new cases of sexually transmitted infection (STI) each year, and female adolescents 15 to 19 years of age account for 24.2 of every 1000 births, 17% of which are repeat births. The provision of evidence-based sexual health curricula is indicated. To be effective, curricula need to be implemented with adequate fidelity to enable students to have exposure to core content. However, successful implementation of sexual health curricula in school settings is often compromised by competing academic priorities. For example, standardized testing schedules can reduce the time available to provide effective sexual health curricula. Thus, it becomes important to understand the association between the quantity and quality of program exposure (or "dose") and students' sexual health behavior. Understanding the required time-on-task (number of lesson-hours) and the type of sexual health topics most associated with delayed sexual initiation may enable the implementation of evidence-based programs within an increasingly "crowded" academic program without compromising their effectiveness.