Quantity: Does This Key Concept Lack a Common Understanding?

• In Event: Measuring Teachers' Mathematical Knowledge and Behaviors

Abstract

Quantitative reasoning is important, and identifying quantities and modeling their interrelationships is fundamental to quantitative reasoning. In professional development (PD) designed to support teachers’ understanding of proportional reasoning, we assumed teachers and math educators worked from a common understanding of the concept of a quantity. Yet, recent PD sessions made us reexamine this assumption. In this paper, we share our definition of “quantity” and use this definition as a lens to examine teachers’ understanding of the concept as evidenced in our PD sessions. We share vignettes featuring different teacher definitions of quantity and propose more attention be paid to how teachers view quantity and how teacher education programs support teachers in developing a robust understanding of this foundational concept.

Authors

• Martha Epstein, University of Massachusetts - Dartmouth

• Chandra H. Orrill, Rethink Learning Labs

• Rachael Eriksen Brown, Pennsylvania State University - Abington