By offering a close reading and interpretation of one conversation between four Year 8 pupils about Robert Swindell's "Stone Cold," I aim to address questions of what might count as knowledge in English and to suggest how it might develop not only out of the qualities of a text, but from particular social relations and a set of pedagogic choices. I argue for a refocusing of attention away from the "acquisition" of "cultural capital" or "powerful disciplinary knowledge" by individual pupils, towards the cultural resources and cultural productivity of pupils and teachers. I go on to suggest that serious consideration of such conversations as evidence of learning poses a significant challenge to dominant theories and research methodologies that locate knowledge and ability within the minds of individual pupils. Instead, my reading of this classroom interaction suggests the creative potential of discussion in diverse, urban classrooms to contribute to a fuller account of learning that pays proper attention to its roots in the social and affective realms. Crucially, part of my argument is that classrooms such as the one in which the conversation took place offer unique opportunities and conditions for the development of a pedagogy that both draws on and negotiates difference and is therefore culturally productive in a wider sense.