This video, produced by WNET, profiles the efforts in two districts, Tulsa, Okla., and Washington, D.C., that have rethought the job of principal supervisors so they can better support principals and help improve instruction in classrooms. The result is that supervisors now are fixtures in Tulsa and D.C. schools, doing things like classroom walkthroughs to observe what’s working and what isn’t—then sitting down with principals to discuss solutions.