School principals have a range of complex roles, but chief among them is instructional leadership. Instructional leadership itself is complex, as principals work at the intersection of standards, supervision approaches, coaching, and policies. Leading learning can be complicated further when principals work with teachers outside of their own areas of content expertise (what we term instructional mismatch). A challenge to empowered instructional leadership is that principals may feel they lack credibility when working with teachers in situations of instructional mismatch (Lochmiller, 2019). One avenue for addressing this challenge is helping principals develop leadership content knowledge — distinct aspects of effective pedagogy that apply to particular content areas (Stein & Nelson, 2003). While no principal can know everything about every content area, all principals can work