The classroom is a micro-culture where socio and socio-mathematical norms of interactions are fostered by an instructor who represents the mathematics community. Informed by the "emergent approach" developed by Cobb and Yackel (1996) that explains how mathematical growth takes place in the social context of classrooms, I explored the enactment of these norms in small groups' interactions that were not directly influenced by an instructor. I used audio recorded and later transcriptions of groups of undergraduate mathematics students' discussions on class tasks that were analysed using Polkinghorne's (1995) narrative analysis. Using excerpts from the discussions I argue that with a broadened view on socio-mathematical norms, and interpretations of interactions that focus on "learning in the moment", enactments of norms are seen in students' (a) contributions to discussions through initiating discussions, (b) taking responsibility for raising and offering answers, (c) acceptance of arguments that are efficient to the self. (Contains 1 figure and 2 tables.)