When the author returned to teaching after several years in graduate school, she came armed with knowledge and visions of a student-centered classroom. Her experiences in a doctoral program taught her much about effective mathematics instruction and rekindled her desire to teach. However, a student-centered classroom reflected a major shift in instruction. Years before when she taught high school mathematics, she had quickly fallen into familiar teaching patterns. The author used a traditional curriculum and found that lecturing while students filled in notes was a manageable and reasonably effective process. This time would be different, however, because she had the opportunity to teach a problem-based curriculum, Connected Mathematics 3 (CMP). The author was determined to offer high-level tasks and maintain cognitive demand, orchestrate meaningful mathematical discussions, and foster effective and equitable group work. Her commitment to student-centered instruction took root in research, but it grew strong because she had seen it done in several classrooms with diverse groups of students. She knew what was possible and embraced strategies that she had observed being used by effective teachers. In this article, the author shares her experience on the challenge of instructional change and three steps she took to changing her practice.