“…The survey items solicit teachers' perceptions on various aspects of their school environments. I selected items that were common in survey versions across years 7 and over which policymakers or school leaders have primary control: principal leadership, mentoring, and professional development (e.g., Boyd et al, 2011;Kraft & Papay, 2014;Ladd, 2011;Loeb, darling-Hammond, & Luczak, 2005;Simons & Johnson, 2015). I then used exploratory factor analysis with the oblique rotation method to obtain relatively independent constructs with eigenvalues >1.…”