\textit{Periscope:} Looking into learning in best-practices physics classrooms

Periscope is a set of instructional materials designed to support university physics instructors -- including teaching assistants, learning assistants, and faculty -- in learning to notice and interpret classroom events the way an accomplished teacher does. Periscope is organized into short lessons that highlight significant questions in the teaching and learning of physics, such as ``How do I bring out students' physics ideas?'' and ``Does it matter if students are unhappy in my class?'' Lessons are centered on captioned video episodes of introductory physics students in best-practices classrooms. By watching and discussing authentic teaching events, instructors enrich their experience with noticing and interpreting student behavior and practice applying lessons learned about teaching to actual teaching situations. Periscope also gives instructors a view of other institutions' transformed courses, which can support and expand the instructors' vision of their own instructional improvement and support the transfer of course developments among faculty. Periscope materials are free to educators.