Purpose: The present thesis aims to gain an insight into pre-school teachers’ perceptions of the relevance of using illustrated books that include representations of same-gender families/relationships and address issues of gender expression that do not follow the normative gender categories in the classroom. The thesis was conducted within the interdisciplinary field of child studies, drawing from a social constructivist viewpoint and having queer theory as a point of departure. Methods: A small-scale, qualitative study was designed, which included semi-structured interviews with pre-school teachers who educate four to six years old children in Greece. Five participants were interviewed, and the interviews were analysed with the use of thematic analysis. The questions asked in the interviews were oriented around the teachers’ reflections on the use of a mentioned book in their classrooms, upon possibilities or difficulties in relation to the use of this kind of literature and finally, their ideas about children, gender and sexuality. Results: The pre-school teachers did not discuss the implementation of pedagogical practices that are driven by interrupting heteronormativity, neither positively nor negatively. They did discuss an unwillingness to address topics about sexual minorities or gender non-conformity within their classrooms, because of the following difficulties: unreadiness, children’s insensibility towards sexual minority topics, societal normative values. Finally, they discussed gender understood as synonymous to sex and through the binary of male and female. Conclusions: The findings of the thesis support the ongoing silencing of some forms of sexuality or gender-related topics in early childhood education. Furthermore, they provide an insight into the difficulties pre-school educators come across when they face the dilemma of addressing topics that challenge heteronormativity. Moreover, the results of the study problematise dominant discourses about children, gender and sexuality. Consequently, this study presents in-depth qualitative knowledge of a small group of pre-school teachers and motivates further research on gender education that Greek children receive.