Abstract
Teaching assistants (TAs) are incredibly important in our teaching but are often under-supported in their roles-particularly in large courses, with large teams. Depending on instructor workload and TA contract hours, it can be challenging to support the professional development of these key members of the teaching team. To help our TAs develop their teaching and engage in a community of practice, we implemented a reciprocal peer observation. By observing each others' tutorials in a structured way, we promoted a sense of community and collaborative learning among the TAs with only a small investment of time by instructors. We structured these peer visits using COPUS-TA, an observational tool that guides their tutorial visit and feedback conversations. From this process, our TAs increased their sense of confidence and community. This is a relatively simple approach to give TAs professional development and connection to their peers, embedded directly within a large-enrollment undergraduate course.