Background: Lack of content knowledge (CK) is problematic in teaching in classroom subject areas and in physical education. There is a dearth of data-based research on interventions aimed at helping teachers acquire CK and, in turn, on the effects of CK on student learning. Aim: To investigate the effect of professional development, in the form of…

Calls to advance students' ability to engage in mathematical reasoning practices including conjecturing, generalising and justifying (CGJ) place significant new demands on teachers. This case study examines how Mathematics Studio provided opportunities for a team of U.S. middle school teachers to learn about these practices and ways to promote…