At all levels of government and across the education and health sectors there has been a proliferation of policy in recent years aimed at improving the mental health and wellbeing of young people. An extensive body of research exists in the areas of youth mental health and wellbeing, matched by increased policy attention to preventative programs and health promotion in schools. The sense of urgency that characterises educational policy internationally is underscored by a large body of research suggesting an increasing prevalence among young people of both serious mental health disorders and more diffuse forms of emotional and psychological distress. Within this context, a key priority of schooling today is to better support the social and emotional development of young people. Building resilience and cultivating social and emotional skills are now regarded as vital complements to the traditional educational aims of knowledge acquisition, vocational preparation and the development of citizenship. This paper begins by tracing the shift from an historically narrow focus on targeted interventions for students experiencing problems or identified at risk of mental health difficulties, to the more recent emphasis on whole school approaches and preventative programs – which encompass health promotion, curriculum initiatives and attempts to cultivate school environments that make young people feel safe and valued. The paper then critically examines policy rationales for current approaches in light of empirical evidence, which is equivocal on the subject of whether school environments and preventative programs affect and improve the wellbeing of young people. The paper concludes with some reflections on the seductive power of ideas of prevention and psychological ‘inoculation’ and considers their implications for educational practice and ultimately for understanding youth wellbeing.