Success and failure in school is contingent upon one's ability to regulate and situate identities, utilise culturally-developed semiotic tools and negotiate models of meaning in shared social activity. However, many language minority students lack such success, struggling with conflicts between their primary-and community-based identities, and existing personal models of the world instantiated through community-based Discourses on the one hand, and discrepant new constructs and literate Discourses, on the other. We compare and contrast linguistic and non-linguistic components of ways of speaking, being, performing and reasoning, within an urban African-American secondary classroom and an African-American mid-western hair salon.We identify culturally-shared interactional norms that inform knowledge building across both sites. We analyse how the Discourse norms and structures of argumentation evident in the hair salon provide participation structures that invite engagement with complex problem solving tasks in both sites. The semiotic potential of these participation structures is heightened in the classroom context by providing scaffolding tasks where students draw on tacit conceptual knowledge constructed from their home/community experiences and that is analogous to the target academic task. (Contains 3 figures.)