This paper explores the relationships between sex, gender and sexuality through a series of close readings of data generated through an ethnography undertaken in a south London secondary school. The paper takes as its focus girls aged 15 to 16 and considers how particular sexed, gendered and sexualized selves are constituted. Drawing on Foucault's understanding of subjectivation and the subsequent work of Judith Butler, in particular her theorization of the inseparability of gender and sexuality in the contemporary discursive frame, these analyses demonstrate how students' mundane and day-to-day practices--including bodily deportment, physical games, linguistic accounts, and uses of clothing, hairstyles and accessories--are implicated in the discursive constitution of student subjectivities. The paper argues for an understanding of sex-gender-sexuality joined together in discursive chains and intersecting with further identity categories. As such, the paper suggests that subjectivities might helpfully be thought in terms of constituting constellations that create both possibilities and constraints for 'who' students can be.