Anti-racist curricula and teaching methods are a potentially potent way for schools to better promote a just society and improve educational outcomes for low-income students and students of color. Ethnic studies (ES) courses in K–12 schools are an increasingly common and prominent example of such culturally relevant and critically engaged practice. Proponents tout the benefits of ES for increasing student engagement and academic outcomes, yet there is little causal evidence supporting these claims. In this study, we use a preregistered regression-discontinuity research design to identify the longer-term impacts on educational attainment and engagement of being assigned to an ES course in grade 9. We find that assignment to ES substantially increased high school graduation, attendance, and the probability of enrolling in college.