Subjects and objects of research and theories of learning in the education and professional development of mathematics teachers

This group report focuses on two key aspects of research on teacher learning in TWG18: (1) what is being studied—the main topics of interest, that is, the subjects and objects of research; and (2) how these topics are investigated—particularly in relation to various theories of learning. Our goal is to map the contributions to CERME14 through these two lenses, offering both a descriptive overview of the current landscape and a critical perspective on our research community. Such a perspective is essential for identifying blind spots, questioning taken-for-granted assumptions, and pushing our collective work forward.