Within educational research, there is a clear distinction between sex and gender. Whereas sex is defined as the biological features that make us male and female, understandings of gender including what is masculine and feminine are socially constructed (World Health Organisation, 2018; Nobelius, 2004). Although the impact of sex and gender on music education has been researched extensively over the past fifty years, the research into boys’ music education has primarily focused on the impact of student gender and physiology on pedagogy and boys’ engagement in music (Young, 2017; Harrison, 2010; Young, 2012). Rarely has this research explored the extent to which the physiology (the sex) of the teacher interacts with gendered stereotypes to affect the teaching of all-boys music. This research project aims to address the gap in the research by exploring to what extent teacher sex and gender affects the teaching of music in all-boys secondary schools. The project employs a mixed-method approach in two stages. Beginning with stage one, a demographic survey was completed in 2019 to establish the distribution of male and female music teachers in all-boys schools across Australia. Stage two began in 2020 and involves semi-structured interviews with male and female music teachers and focus groups with adolescent male music students in all-boys schools. The purpose of these interviews and focus groups is to better understand the pedagogy and approach female teachers use when teaching all-boys in comparison to male music teachers in all-boys schools. This paper will present the complete findings of the stage one demographic survey and explore, with reference to the literature, the emerging themes from the stage two interviews and focus groups. References: Harrison, S. (2010). Boys on the Outer. Boyhood Studies, 4(1), 39-53. Nobelius, A. (2004). What is the difference between sex and gender? Retrieved from http://www.med.monash.edu.au/gendermed/sexandgender.html World Health Organization. (2018). Gender. Retrieved from http://www.who.int/gender-equity-rights/understanding/gender-definition/en/ Young, A. (2012). The courage to sing: Reflections on secondary school singing. In Perspectives on Males and Singing (pp. 311-323). Springer, Dordrecht. Young, A. (2017 published). Teaching Boys Music in the First Year of Secondary School: Discerning and Improving Attitudes of Young Male Students to Singing and Learning in Classroom Music. (Doctoral dissertation).