We designed a video-based course to develop preservice teachers' vision of ambitious instruction by decomposing instruction to learn to attend to student thinking and to examine how particular teaching moves influence student learning. In this study, we examine the influence that learning to systematically analyze ambitious pedagogy in the course has on preservice teachers' classroom practice. Analysis of preservice teachers' videos from the Performance Assessment for California Teachers Teaching Event reveals that they engaged in more student-centered practices compared with a cohort of candidates who did not participate in the course--creating opportunities to see student thinking, noticing student thinking during instruction, and pursuing student ideas to learn more about their thinking. We also found that their probing of student thinking focused primarily on correct answers and procedural fluency. These findings have implications for defining a pedagogy of teacher preparation to develop beginning teacher competency.