We report on an observation of a lesson where students were working on geometrical pattern tasks in pairs. The teacher’s intentions for the paired setting and his reflections upon seeing a video of the lesson are presented, and through the lens of a TRU analysis and the Knowledge Quartet, we identify potential for exploiting the task and the environment to afford students’ mathematical engagement. We focus on the interplay between the Contingency and Foundation dimensions in the Knowledge Quartet, and the potential of developing retrospective awareness into in-the-moment awareness.