As a lens through which to read and understand a subject area and its curriculum content and issues, a sociocultural perspective is a recent and arguably significant change for the Health and Physical Education (HPE) Key Learning Area (KLA) in Australia. Its significance lies, first, in the fact that it seems to represent a notable departure from the predominantly medico-scientific, bio-physical and even psychological foundations of the learning area as it stood throughout the second half of the twentieth century, and second, because its attention to social and cultural influences on health put it in direct opposition to notions which locate health almost solely in the individual and his or her decisions. Despite the potential ramifications of these shifts for practitioners, to date there has been little research that has examined this change within the context of the classroom. This paper reports on a research project conducted in two classrooms in the Australian state of New South Wales, which began with the question 'what happens when you introduce a unit of work planned with the aim of developing a sociocultural perspective into the HPE classroom?' I respond to this question by drawing on teacher and student interviews, planning sessions, and classroom observations and recordings to discuss the most prominent discursive tensions and organisational constraints that stand as impediments to a sociocultural perspective as a practiced curriculum change.