Research exploring the educational relevance of wellbeing only tentatively confronts the 'tension' of expecting educators to nurture pupils' wellbeing while school effectiveness is evaluated by metrics of academic performance. Complete wellbeing includes hedonia (feeling) and eudaimonia (doing) well. Accordingly, school 'happiness agendas' overlook the latter, despite psychologists suggesting eudaimonia ('welldoing') is foundational for wellbeing, particularly in adolescence. Rooted in Aristotlean ideas of 'living and doing well', philosophers underline eudaimonia's educational significance. However, high-stakes testing undermines eudaimonia, with England's performativity culture representing a barrier. Recently scholars have called for 'stronger evidence' documenting links between adolescent mental illness and academic pressures. The present study therefore explored 18 adolescents' (14-15 years' old) lived experiences of wellbeing in one English state school. Although existing studies document adolescents' "conceptualisations" of 'wellbeing', adolescents' "lived experiences," particularly of eudaimonia and specifically in school, are comparatively absent. Interviews adopting a phenomenological approach therefore investigated (1) "how" adolescents experience wellbeing, and (2) what 'doing well' at school means to adolescents. Adolescents' welldoing experiences did not resemble eudaimonia, which involves individuals connecting with personal purpose through cultivation of their unique abilities. Instead, welldoing at school was instrumentalised as obtaining good grades. Although hedonia was reflected in adolescents' experiences, hedonia was intrinsically connected to welldoing, with mental health attributed to achieving 'good' or 'bad' grades, respectively. Recommendations include the need for wholescale integration of wellbeing into education in England, which requires (1) overhauling educational aims to focus on supporting individual flourishing as opposed to academic standards, and (2) de-emphasising harmful performativity culture.