Some argue that the goal of education is to influence out-of-school learning activity, yet little research exists on how teachers can help students develop an interest in a topic and continue to pursue that interest outside of school. The current study tested classroom context variables from self-determination theory (teachers' autonomy support) and from achievement goal theory (teachers' mastery goals) that may predict students' school-prompted interest above and beyond students' mastery goals and self-efficacy. Survey data were collected from 178 high school students in 15 mathematics classes. Hierarchical multiple regression revealed that students' perceptions of a teacher who focuses on mastery goals account for little variance above and beyond students' own motivation, whereas perceived teachers' autonomy support emerged as a significant predictor. While the results are correlational and do not support causal claims, they suggest that teachers who support student autonomy might foster school-prompted interest. (Contains 3 tables and 3 notes.)