This paper is concerned with the relationships between students' social identities, their experiences of schooling and educational exclusion. Drawing on data generated through an ethnographic study in a comprehensive public high school in outer-Western Sydney, the paper demonstrates the nuanced institutional and interpersonal processes through which particular young people come to be constituted as impossible students. In doing this, the paper focuses on a mixed-age boys' 'Special Sport' class. Drawing on Gillborn and Youdell's (2000) notion of 'educational triage', as developed in relation to educational practices in the UK, the analysis offered demonstrates the significance and applicability of the 'educational triage' model to educational settings beyond the UK. Specifically, this study identifies and interrogates those practices that limit the educational resources to which this group of students has access and, in so doing, function in the production and maintenance of marginalized identities. Furthermore, the analysis suggests that the group's perceived inability to negotiate successfully the prevailing masculinist assumptions and practices that pervade the school is crucial to these discursive locations. Consequently, at every level of institutional discursive practice, both the students and teacher of the class are constituted as substandard members of the school community.