The aim of this qualitative study was to analyse gendered strategies among pupils in the negotiation of power at school, and to discuss possible implications for health. Twenty-seven single-sex focus group interviews were conducted with pupils from equal opportunity projects The interviews were analysed using grounded theory. The girls used 'alliance building' and 'resistance: in order to increase their power, while 'responsibility taking' and 'withdrawal' could mean maintained subordination. The boys used mastering techniques (various types of abuse, claiming to be the norm, acting-out behaviour, blaming the girls, choosing boys only) in self-interest to maintain their dominance. The girls' active and democratic actions far increased power could be of significant importance for their health. The boys' health would benefit if they gave up striving for power over others School health promotion needs to address the asymmetric and gendered distribution of power between pupils, as well as to challenge the existing gender regime at an institutional level.