“…Fundamentally, mathematicians engage in their daily instructional practice based on their experience as learners and teachers-they are teaching a specific audience in a specific subject and consider what they consider to be "normal" classroom activity for the course in designing their lessons. For example, there is a "convergence" around the "right" number of homework problems to assign in a proof-based class (c.f., Rupnow et al, 2021), that balances the desire to promote student understanding with their willingness and ability to complete the work. Similarly, the genre of chalk-talk is remarkably similar across cultures and countries, and within the United States lectures are generally very similar in terms of structure, pacing, and the types of content and pedagogical practices engaged (c.f., Artemeva and Fox, 2011;Fukawa-Connelly et al, 2017;Johnson et al, 2018).…”