This paper explores the effects of specific teacher threshold knowledges about boys and gender on the implementation of a so-called 'boy friendly' curriculum at one junior secondary high school in Australia. Through semi-structured interviews with selected staff at the school, it examines the normalizing assumptions and 'truth claims' about boys, as gendered subjects, which drive the pedagogical impetus for such a curriculum initiative. This research raises crucial questions about the need for the formulation of both school and governmental policy grounded in sound researchbased knowledge about the social construction of gender and its impact on the lives of both boys and girls and their experiences of schooling. This is crucial, we argue, in light of the recent parliamentary report on boys' education in Australia which rejects gender theorizing and given the failure of key staff in the research school to interrogate the binary ways in which masculinity and femininity are socially constructed and institutionalized in schools through a particular 'gender regime'. While some good things are happening in the research school, the failure to acknowledge the social construction of gender means that ultimately the school's programs cannot be successful.