Objective: School Health Profiles (Profiles) is a national surveillance system operated by the US Centers for Disease Control and Prevention. A school-based system of surveys, Profiles monitors school health policies and practices in US states and other jurisdictions through questionnaires completed by school principals and lead health education teachers. This study used the Profiles principal survey to identify trends in US schools' implementation of diversity-related learning opportunities (i.e. opportunities to learn about people who are different from themselves) in secondary school classrooms and extracurricular settings. Methods: Logistic regression models using data from three cycles of School Health Profiles from 35 US states examined trends in the percentages of secondary schools offering students diversity-related learning opportunities in the following settings, each measured by using dichotomous yes/no response options--(a) clubs; (b) lessons in class and (c) special events (e.g. multicultural week, family night) sponsored by the school or community organisations. Results: Between 2014-2018, no states experienced decreases in opportunities for students to learn about people who are different from themselves; most states demonstrated no significant change. Conclusion: Findings suggest efforts are needed to strengthen capacity for and prioritisation of policies, programmes and practices promoting diversity and culturally relevant education in schools, and in turn, promote positive health and educational outcomes for youth.