Over the last decade the school setting has emerged as a crucial site for the promotion and maintenance of children and young people's health. Issues relating to the types of foods served in and around schools continue to dominate school health policy and occupy a central position in government attempts to avert impending public health crises expected to arise from the perceived 'obesity pandemic'. While acknowledging the ways in which school food has become a lens employed to focus the medical gaze towards the regulation of children's bodies, we need to be mindful of the tendency to regard these bodies as 'docile' and children as passive targets of school food policy. Rather, this piece seeks to problematise this view, seeking instead to develop an understanding of school dining rooms as spaces in which traditional power relationships between adults and children are contested and renegotiated. Data are drawn from an ethnographic study of four primary schools in Kingston upon Hull to explicate the contested nature of power relationships played out between teachers, lunchtime staff and pupils within the spatial and temporal boundaries of the dining room. In conclusion the argument is made that policy relating to school food is mediated by power relationships within schools. Rather than operating on static axes of power, these dynamic relationships constantly shift and are continuously renegotiated, redefined and contested.