In this article, the author reports on a participant-observation case study that explored how alternatively certified, middle school teachers' expectations of tracked students affect their ability to learn to teach in ways that promote students' mathematical struggle and participation in productive mathematical discussions. Two teachers--one teaching a "high-tracked" course and the other a "low-tracked" course--were participants. Both teachers initially held perceptions of their students that limited their efficacy and self-efficacy with respect to providing high-quality mathematics instruction. However, through program- and school-based mentoring, including participation in a modified reflective-teaching cycle, the teachers learned to learn from their teaching and modify their practice. Both teachers began to allow their students opportunities to struggle with rigorous mathematics and participate in student-centered discussion.