The present study tested a model showing how different aspects of high school courses focusing on social justice and prosocial development predicted prosocial intentions of students (N = 362) 2 to 29 years after they had completed the courses. Results indicated that students reporting more transformative class experiences (higher critical self-reflection, more charismatic forms of instruction, and relatable course content and methods) were significantly higher on prosocial intentions than students who did not. Unexpectedly, more well-integrated service learning did not directly predict higher prosocial intentions. Implications for gender and SES were explored. Overall, results suggest that certain parts of such classes can predict prosocial development.