Measuring the Effects of Professional Development on Teacher Knowledge: The Case of Developing Mathematical Ideas

TLDR

This study investigates how the nationally disseminated Developing Mathematical Ideas program influences teachers’ specialized mathematics knowledge and explores how program features, facilitator experience, and scale affect knowledge gains. The study compared teachers who completed two DMI modules with comparable non‑participants, assessing knowledge through multiple‑choice and open‑ended items developed by the Learning Mathematics for Teaching project and DMI experts. Controlling for pretest scores, teachers who completed DMI performed significantly better on both assessments, and higher facilitator experience with DMI was associated with greater gains on the more aligned measure. The paper discusses study limitations and challenges.

Abstract

This study examines the impact of a nationally disseminated professional development program, Developing Mathematical Ideas (DMI), on teachers' specialized knowledge for teaching mathematics and illustrates how such research could be conducted. Participants completing 2 DMI modules were compared with similar colleagues who had not taken DMI. Teacher knowledge was measured with multiple-choice items developed by the Learning Mathematics for Teaching project and open-ended items based on problems initially developed by DMI experts. After controlling for pretest scores, a hierarchical linear model identified statistically significant differences: The DMI group outperformed the comparison group on both assessments. Gains in teachers' scores on the more closely aligned measure were related to the degree of facilitator experience with DMI. This study adds to our understanding of the ways in which professional development program features, facilitators, and issues of scale interact in the development of teachers' mathematical knowledge for teaching. Study limitations and challenges are discussed.