Bringing an awareness of emotions to the fore through mindfulness-based breathing and providing a space to discuss them is a way of promoting teacher and student agency in collectively developing structures specific to their learning environment. The authors explore students', teachers', and researchers' collective sensemaking through cogenerative dialoguing (cogen) about a mindfulness-based breathing practice at the start of mathematics lessons in an elementary classroom. They found that the power of cogen as hybridized space enabled the generation of collective understanding and the potential for all cogen participants to become engaged in an authentic and transformative way in discussing classroom life. The authors argue that the mindfulness-based breathing practice itself acted as a heuristic for thinking about learning environments and, during the reflexive process of thinking about the breathing practice, new forms of classroom culture unfolded both expanding classroom structures and the practice itself, and laying bare otherwise taken-for-granted practices.