Early school-leaving imposes costs on the individual and society, and is linked to factors including gender, family income and parental education, community deprivation, and academic history. In Ireland, the role of the school in shaping patterns of early school-leaving is unclear. Employing the Theory of Planned Behaviour (TPB) from social psychology, variation by school among Junior Certificate students in the intention to leave early was assessed, along with characteristics of the individual school and its students. Twenty Irish second-level schools were selected by systematic random sampling. All students in Junior Certificate year were asked to participate, of whom 68.84% (1131) did. Participants completed a questionnaire on intention to drop out of school, three components of the TPB in relation to school completion, demographic details, and academic results. There was evidence of a within-school culture or group representation of the value of education shaping the students' intentions around school completion. (Contains 2 figures and 2 tables.)