In this paper, the authors consider how Carol Dweck's concept of growth mindset has been misconceptualised. They explore the proposition that agency is an important aspect of growth mindset and that the effects of hard work by children is reduced when agency is limited. They draw on qualitative data from 84 interviews with 23 participant children who had been designated at the end of their Year 3 as 'lower-attainers' in mathematics, English or both. They explore their experiences of this designation across the first two years of the five-year project. Their findings suggested that participants displayed ample capacity for action, curiosity, engagement and creative learning. However, classroom rules sometimes mitigated against children benefiting from these capacities. Children narrated adopting the performance orientation suggested by Dweck, which could lead to a reduced sense of competence, which itself led to less agentic classroom behaviours.