3: Adapting Cases from a Developing Mathematical Ideas Seminar to Examine the Work of Teaching Closely

This chapter describes three uses of cases from the Building a System of Tens (BST) seminar. BST is one of seven modules available in the Developing Mathematical Ideas professional education materials (Schifter, Bastable, & Russell, 1999). BST is designed to support elementary teachers in analyzing how students develop a robust understanding of the base-ten system. The cases help seminar teachers learn how students’ thinking develops when they are given opportunities to share and explore their understanding and their confusions. We describe how we have used particular cases to achieve a focused set of goals especially targeted for teachers who are beginning to learn to build instruction on students’ thinking. We explain how our strategic use of cases brings to the surface the significant work that teachers do when they design tasks and anticipate, elicit, and respond to students’ mathematical ideas.