This exploratory study measured the sexuality education and HIV knowledge, attitudes, and risk behaviors of young adults (n = 410), ages 18-21, who recently graduated from public high schools in a midwestern state. Based on the participants' responses to specific questions, students were placed into one of three groups: students who received no sexuality education; students who received abstinence-only sexuality education; and students who received abstinence-based sexuality education. Students who reported having completed an abstinence-based sexuality education scored significantly higher on HIV knowledge, attitudes, and behaviors than those who reported receiving an abstinence-only sexuality education (p less than 0.001). The mean scores on the HIV risk behavior scale were also significantly higher in the no sexuality education group when compared to the abstinence-only group (a higher score represented less risk-avoidance of risk behaviors). (Contains 3 tables and 1 footnote.)