References from the episode: Herbst, P., & Chazan, D. (2003). Exploring the practical rationality of mathematics teaching through conversations about videotaped episodes: The case of engaging students in proving. For the Learning of Mathematics, 23(1), 2-14. [Goal mapping] Herbel-Eisenmann, B. A., & Cirillo, M. (2009). Promoting purposeful discourse: Teacher research in mathematics classrooms. Reston, VA: NCTM.