This article suggests that citizenship should be seen not as a status to be acquired, lost or refused by an individual. Rather it is an emergent and relational capacity produced and reproduced in everyday material interactions, across a spectrum of activities from work to lifestyle practices. We examine one example of such a material interaction: the engagements that young people have with sexualities education. To aid this endeavour, we apply a new materialist, relational framework that addresses the micropolitical interactions between humans and non-human materialities. Using data from two studies of sexualities education, we assess how the capacities produced during sexualities education interactions – such as a capacity to express specific sexual desires or to manage fertility proactively – contribute inter alia to young people’s ‘becomingcitizen’. Informed by this analysis, we argue that sociology may usefully apply a bottom–up model of citizenship as becoming, constituted materially from diverse engagements.