Self-determination theory provided the theoretical framework for a cross-sectional investigation of elementary and junior high school students' autonomous motivation for homework. More specifically, the study focused on the role of teachers' support of students' psychological needs in students' motivation for homework in the two school systems. The study also investigated the contribution of a match between teachers' support and students' expressed level of psychological needs to autonomous motivation for homework. The findings indicated that teacher support partially mediated the difference in autonomous motivation for homework between students in the two school systems. In addition, the findings suggested that whereas students' with different level of expressed needs may perceive different levels of teachers' support, and that teachers' support might be more important for students who express higher level of needs, perceived teachers' support of psychological needs was important for students' adaptive motivation for homework, irrespective of their expressed level of needs. (Contains 3 tables and 3 figures.)