Using and developing content-related theory elements for explaining and promoting teachers’ professional growth in collaborative groups

What kind of theory is required to explain and promote teachers’ professional growth in collaborative groups? Sociocultural theoretical frameworks and models of professional growth have been successfully established as powerful generic frameworks (partially mathematics specific, but not yet content specific). The chapter argues that these generic frameworks should be further refined in content-related ways, so that both types of content, the mathematical classroom content and the mathematics education PD content, are more explicitly part of the research and the designs. Whereas the generic frameworks already exist and can be used, the refinement requires acts of content related theorizing, which means developing and connecting content-specific theory elements. These theory elements refer to several areas that can be located in the tetrahedron model: Theory elements are not only required for explaining and enhancing the PD environment and facilitation practices, but also for explaining and enhancing the content-specific teacher learning that also requires theory elements for the PD content itself to unpack it into relevant aspects of the classroom learning environment, the teaching practices, the student learning, and the mathematical content in view. Different content-related theory elements are presented and exemplified for a vignette showing the professional growth of a collaborative group of middle school teachers aiming at differentiating and fostering at-risk students’ access to mathematics.