Introduction THERE IS A WIDESPREAD BELIEF that children either do not or should not know about sexuality, and attempts to engage with young children around issues of sexuality is problematic in the early years (Epstein, 1999; Renold, 2005; Robinson, 2005; Sears, 2009; Tobin, 1997). Cullen and Sandy (2009) argue that dominant and romantic discourses of presumed childhood innocence (James, Jenks & Prout, 1998) construct young children as naive, with little knowledge about gender and sexuality. This is a common idea that has been supported by some research. For example, in the health sciences, Brilleslijper-Kater and Baartman (2000) investigated the sexual knowledge of 63 Dutch children (two- to six-year-olds) and determined that they only had a basic grasp of sexuality. This project defined sexual knowledge as children's ability to determine sex differences; name sexual body parts and functions; and describe what they knew about the birth process, reproduction, and adult heterosexual behaviours. Although children in the study showed evidence of talking about adult heterosexual behaviours, such as males and females kissing each other or cuddling, the authors conclude that children's ability to understand the differences between physical intimacy and heterosexual interactions does not play a significant part in contributing to children's sexual knowledge. On the other hand, there is gender and sexuality research situated within the sociology of education, drawing from poststructuralist and queer theories, arguing that children's understandings about gender differences and heterosexual interactions, even ones that might not appear to be about sexuality per se, are significant and do show that young children have sexual knowledge. These perspectives consider gender and sexuality to be socially constructed and have rethought the relationship between sex, gender and sexuality in ways that show how gender and sexuality are deeply interrelated. Research conducted in education shows how children use their knowledge of gender norms and (hetero)sexuality to regulate and construct what it means to be a girl and boy (Blaise, 2005, 2009; Blaise & Andrew, 2005; Bhana, 2007; Davies, 2003; Francis, 1998; Grieshaber, 2004; Reay, 2001; Reneld, 2005; Skattebol, 2006; Taylor & Richardson, 2005; Tobin, 1997). Attempting to resolve these two competing discourses about children's sexual knowledge and its role in identity construction, a small-scale qualitative study framed by poststructuralist and queer perspectives was conducted over a five-day period. This project set out to explore how young children talk about gender and sexuality while engaging with activities commonly found in early years' settings.