Mathematically Important Pedagogical Opportunities Dr. Laura Van Zoest The mathematics education community values using student thinking to develop mathematical concepts, but the nuances of this practice are not clearly understood. For example, not all student thinking provides the basis for productive discussions. My colleagues and I are working on a conceptualization of instances in a classroom lesson that provide the teacher with opportunities to extend or change the nature of students’ mathematical understanding—what we refer to as Mathematically Important Pedagogical Opportunities (MIPOs). Attached is a draft of a paper that describes this construct. In seminar we will test out the MIPO construct by applying it to excerpts of classroom dialogue from the mathematics education literature.