Sexual health education is a well-known, evidence-based intervention that can improve adolescent health outcomes, increase protective health behaviours, and decrease risky health behaviours. Providing sexual health education in schools offers opportunities to discuss critical health topics and can improve the school environment. However, not all sexual health education is taught equitably. As part of a mixed-methods study to describe school-based sexual health education, we conducted focus groups and interviews with recent high school graduates in a geographically and ethnically diverse state in the US Southwest. Thirty-one young people shared their experiences, explored the content they had been taught, and offered recommendations to improve sexual health education. Three key themes emerged: young people wanted and needed sexual health education taught in school; current sexual health education is not helpful and sometimes harmful; and the individuals who teach sexual health education are critically important. These findings can help address barriers to school-based sexual health education delivery, particularly for schools within communities with limited resources. The results support including youth as stakeholders in the planning and evaluation of school-based sexual health education, and the development of sexual health education teacher training with the goal of improving youth health outcomes.