ABSTRACT Number Talks are increasingly used in classrooms to support student’s number sense. While Matney et al. (2020) documented little empirical evidence about the effectiveness of Number Talks in improving student outcomes, we considered the potential benefits of Number Talks for teachers and their practices. We ask to which of NCTM’s Mathematical Teaching Practices do pre-service teachers attend while reflecting on Number Talks implemented in a field placement and what was the nature of their attention? Using a constructivist lens, we analyzed the reflections of ten pre-service elementary teachers on three Number Talks in a field placement. As they implemented Number Talks, the participants in this study constructed their own understanding of both the process and purpose of a Number Talk. By doing so, we found that not only was it possible for pre-service teachers to attend to each of the Mathematical Teaching Practices, but three practices were regularly attended to by participants: posing purposeful questions, facilitating mathematical discourse, and supporting productive struggle. Thus, Number Talks may serve pre-service teachers as important vehicles for developing these practices.