Recent developments in the sociology of childhood highlight the structural location of children relative to adults in modern societies and stress the importance of taking account of children's perspectives and views in all matters that concern them (James and Prout 2004, Mayall 2002, Qvortrup 1994). Such perspectives dovetail with ethnographic research that has been conducted over the years in the sociology of education, documenting aspects of the school experience from the perspective of the child (e.g.Connolly 1998, Hammersly and Woods 1984, Filer and Pollard 2000, Pollard 1985, Woods 1990) and the impact this has on educational identity and achievement. Coinciding with such research has also been work that focuses on aspects of children's play in school, including the impact of such play on the formation of gendered and ethnic identities (e.g Opie 1993, Smith 1997, Thorne 1993, Troyna and Hatcher 1990). While much of children's school experience is framed by adult goals and expectations, as active agents children filter their learning through the lens of child culture, simultaneously satisfying/rejecting adult demands for work and effort while positioning themselves with respect to their peers. Through child culture, children construct a world that is separate and autonomous from that of adults. In this sense child culture is an important factor mediating children's experience of adult control. However it is also serves the important function of rendering the world safe and predictable through adherence to a wide range of rituals and conventions that are defined by children themselves. This paper explores the nature of child culture among children in a sample of Irish primary schools. Drawing on ethnographic research (involving interviews, socio-metric analyses, observation and immersion in the school sites over a sustained period) conducted across two studies, it presents a theoretical framework, within which we can begin to understand how children negotiate their social world in school - counterbalancing the demands of 'adult' defined learning (through a nationally prescribed curriculum) with the dynamics of inclusion and exclusion in their peer groups. Key influences include Foucault (1979), Goffman (1971) and Giddens (1984) as concepts related to power, agency and the use of time and space cut across children's experience with adults and peers in school. Identity and the agency of children are key to the analysis as they are shown to position themselves with respect to one another and adults in terms of their gender, ethnicity, ability, sexuality and social class. This positioning influences and cuts across how children react to and experience the curriculum, evaluation and pedagogical practices in school. The paper will take two particular identity indicators, that of ethnicity and ability ('being smart'), as exemplars of children's complex and dynamic interaction in school. In so doing the paper identifies children's capacities as active agents and asserts their critical and reflective skills as they negotiate their path through their social world, a world that is mostly unseen by adults/teachers, yet which forms a core element of children's learning and experience of school.