This project is rooted in decades of content-based professional development focused on developing teachers’ MHoM. In particular, since 2003 we have been engaged in an NSF funded Mathematics Science Partnership, Focus on Mathematics. Throughout this project, teachers reported changes in the way they thought about and taught mathematics. Our evaluators at PERG found evidence of the impact of the MSP on participating teachers, schools, and students. For example, over 10,000 students in the Boston area created original projects for school Math Fairs. But we wanted to know if we were having an impact on teachers’ MHoM. We couldn’t find tools to measure MHoM, so we decided to create them for ourselves. Our goal was not to create assessments of individual teachers but to create something we could use for our own learning about professional development. We were also curious about possible links between how teachers use MHoM for themselves and how they bring those MHoM to bear in their classrooms.

With the introduction of the Common Core State Standards in Mathematics, other projects began asking if they could use our instruments to measure the impact of their professional development on teachers’ use of the Standards for Mathematical Practice, which are closely aligned with MHoM. We felt a responsibility to create an assessment tool that was valid and reliable to share with others. With funds from the NSF’s DRK-12 program, we are now working to create an assessment that is valid, reliable, and usable. We are also beginning to study links between teachers’ knowledge and use of MHoM in their own mathematical work and their classroom use of those MHoM.