Within the sociocultural theoretical framework that this paper adopts, learning, including second-language learning, is conceptualised as increasing participation in a community of practice. Thus it becomes of central importance to examine the nature of the community itself and the kinds of participatory opportunities that it supports or discourages. For it is through their engagement in the specific practices of their communities that students appropriate the knowledgeable skills that these practices involve. In this paper, based on the findings of an exploratory ethnographic study conducted in a US middle school, I examine the learning opportunities created for adolescent English language learners in three different classrooms and the ways in which these students took up these opportunities. I argue that, in addition to the particular subject matter to be taught, what appears to shape the kinds of learning opportunities afforded to English language learners is: (a) teachers' conceptualisation of the needs of second-language students; (b) the ways in which they perceive their own role in responding to these needs; and (c) the larger context of institutional practices.In the past decades there has been growing recognition in the human sciences of the fundamentally social nature of learning and cognition. Paralleling this conceptual shift, in place of the prevailing term 'acquisition', the term 'participation' has come to be used to characterise learning in order to emphasise its social nature. If learning is considered as increasing participation in a community of practice, then it becomes of central importance to examine the nature of the community itself and the kinds of participatory opportunities it supports or discourages. For it is through their engagement in the specific practices of their communities that students appropriate the knowledgeable skills that these practices involve. In this paper, based on the findings of an exploratory ethnographic study conducted in a US middle school, I consider the learning opportunities created for English language learners (ELLs) in three different classrooms and the ways in which the students took up these opportunities. 1 I argue that, in addition to the particular subject matter to be taught, what appears to shape the kinds of learning opportunities afforded to English language learners is: (1) teachers' conceptualisation of the needs of second-language students; (2) the ways in