Transgender students are often an invisible minority in postsecondary education, particularly in STEM fields. I am addressing the lack of research in this area with an exploratory narrative study designed to answer two questions: (1) How have the experiences of postsecondary transgender students in STEM education varied with their gender presentation? (2) How do their experiences with mathematics compare with other STEM fields? I conducted a sequence of three interviews each with three participants to gather information about their life histories relating to gender and STEM. This information was then restoried utilizing the three-dimensional space of narrative inquiry proposed by Clandinin and Connelly (2000). Participants received less respect from their peers while presenting as female, particularly in electrical engineering. Agricultural classes were not perceived as a safe place to be visibly queer, while women's studies were. Mathematics education is a less masculine environment than mathematics, where there is less pressure to conform to masculine standards such as not admitting one's mistakes. Experiences of privilege were sometimes negative if it was accorded on the basis of an identity that felt dysphoric, while experiences of oppression were sometimes positive if they were interpreted as an affirmation of one's identity. Mathematics was seen as more abstract than other STEM fields, which can be a more masculine aspect. However, every participant reported positive affective experiences with female math teachers, which may have mitigated their perception of mathematics as masculine. The college environment served as a prism that refracted gender and revealed a spectrum of gender identities where only a binary had previously been visible. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]