This study examined the links among students' effort, tracking, and students' achievement. It found that students in higher tracks exert substantially more effort than do students in lower tracks. These differences in effort are largely explained by differences in prior effort and achievement, as well as students' experiences in their classes. Students' effort is strongly related to students' learning, and track differences in students' effort account for a modest portion of track differences in students' learning. Finally, the effect of students' effort on students' learning is roughly the same, regardless of the track in which a student is placed.