This article explores three processes involved in attending to evidence of students' thinking, one of the Mathematics Teaching Practices in Principles to Actions: Ensuring Mathematical Success for All. These processes, explored during an activity on proportional relationships, are discussed in this article, another installment in the series.
Miriam Sherin, msherin@northwestern.edu, is a Professor of Learning Sciences in the School of Education and Social Policy at Northwestern University in Evanston, Illinois. Her interests include mathematics teaching and learning, teacher cognition, and the use of video for teacher learning.