Are mathematics teachers with high pedagogical content knowledge inequitably allocated? Evidence from six U.S. urban public school districts

Motivated by concerns about the systematic inequality in students’ access to highly knowledgeable mathematics teachers and the resulting unequal mathematics learning opportunities for students, this study investigated whether mathematics teachers’ pedagogical content knowledge (PCK) was systematically sorted by prior performance and student composition between classrooms within schools and between schools. While prior research has well documented disparities in access to qualified mathematics teachers, few have directly measured teacher knowledge or explored its sorting both within and between schools. This study cautioned against using conventional qualification indicators as proxies for PCK and employed an item response theory-based measure of PCK and hierarchical generalised linear modelling to analyse data from six urban school districts, thereby addressing these limitations. The findings offered new insights into allocation patterns of PCK that can lead to educational inequity and highlighted the importance of using improved measures of PCK in teacher effectiveness research.