Periscope: Looking into learning in best-practices physics classrooms

\textit{Periscope} is a set of materials to support university instructors in observing, discussing, and reflecting on best practices in university instruction. Periscope is organized into short ``video workshops,'' each introducing a significant topic in the teaching and learning of physics, such as formative assessment or cooperative learning. The workshops are appropriate for university professors, two-year college faculty, graduate student teaching assistants, and undergraduate learning assistants. Key topics in teaching and learning are introduced through captioned video episodes of introductory physics students in the classroom, chosen to prompt collaborative discussion. Video episodes from exemplary sites (including the University of Maryland, University of Colorado -- Boulder, Harvard University, and Florida International University) showcase a variety of research-tested instructional formats such as \textit{Peer Instruction} and \textit{Tutorials in Introductory Physics.} Discussion questions prompt participants who view the episode to reflect on their pedagogical beliefs, on their own practice, and on the results of physics education research. \textit{Periscope} materials may be flexibly adapted for settings ranging from brief introductory sessions to all-day workshops or weekly meetings.