"Resilience" has become a popular goal in research, social policy, intervention design and implementation. Reinforced by its conceptual and political slipperiness, resilience has become a key construct in school-based, universal interventions that aim to develop it as part of social and emotional competence or emotional well-being. Drawing on a case study of a popular behavioural programme used widely in British and American primary schools, this paper uses a critical social understanding that combines bio-scientific and social constructionist ideas in order to evaluate key challenges for policy, research and practice framed around resilience. The paper argues that although critical social perspectives illuminate important contemporary manifestations of old problems with behavioural interventions, and challenge narrow, moralising definitions of "risk" and "vulnerability", they coalesce with behavioural perspectives in a search for better state-sponsored responses to the shared question of how to build resilience amongst "vulnerable" groups and individuals. Instead, we argue that critical sociologists need to resist responses that offer more sophisticated behavioural interventions and generate new forms of governance and subjectivity.