ABSTRACT
The number of mathematics coaches in schools has been increasing, but evidence is needed to support policy decisions on the use of mathematics coaches and their work in schools with teachers and students. These questions of policy and practice require instrument design and development to advance research about mathematics coaching. Additionally, research is needed to simultaneously understand mathematics coaching and develop instruments that can validly and reliably document mathematics coaching practices. The purpose of this chapter is to examine existing frameworks and instruments, identify challenges associated with capturing this nuanced work, and provide a call to action in the mathematics education community for the development of rigorous, quantitative measures that have potential to inform the mathematics coaching research and practitioner communities.
