This thesis explores what's possible in terms of affirming sexual diversity in two New Zealand case study schools, Takehe High School and Kereru Girls' College, between 1996 and 1998. The research process was characterised by a number of shifts that arose in the interests of theoretical width and also because of methodological necessity. Initially the research project was developed within an affirmative action model. However over time, the study increasingly became informed by Foncauldian, queer and feminist post-structural frameworks. These theoretical paradigms provided a way to move beyond framing lesbian and gay students in schools as a disadvantaged minority group with personal deficits. The frameworks were also helpful in focusing on the ways in which heteronormative discourses are produced and destabilised within the two case study schools. In addition, Foucauldian, queer and feminist post-structural frameworks provided ways to explore the complex and mutable nature of sexuality, and possible pedagogical directions for students to be able to explore the discursive construction of sexuality and gender in the classroom. Foucauldian analytical tools such as genealogy also proved helpful in accounting for the constraints that arose in the second case study school because of the presence of the project in the school. The final stage of the research process led to what I am describing as an informed action approach. Foucauldian, queer and feminist post-structural frameworks may provide helpful (if challenging) directions in terms of addressing sexual diversity within the formal curriculum. However, I also suggest that affirming sexual diversity in schools should also involve having an understanding of the ideological, structural and micro and macro contextual constraints that will arise when issues of sexual diversity are explored within school contexts. This joint approach may go some way to ensuring that action to affirm sexual diversity in schools can be well informed.