This paper considers the construction and experience of racisms among a sample of primary school children in Ireland during a period of intensive immigration. Placing children's voices at the centre of the analysis, it explores how children's constructions draw upon discourses of "norm" and "other" in relation to national identity and cultural belonging. Constructions of minority ethnic groups are located within a context that defines what it is to be Irish, such constructions carrying with them assumptions related not only to skin colour but also to lifestyle, language, and religious belief. Drawing on key concepts related to power, social identities and child cultures, the findings highlight the significance of ethnic identity to children's negotiations around inclusion and exclusion in their peer groups. Name-calling in general, and racist name-calling in particular, was shown to be an important tool used by some children in the assertion of their status with one another. The sensitivity displayed by the majority ethnic children to skin colour only, in their discussions around racism, highlights the salience of colour to many of these children's typification of themselves as white Irish, and of many black migrant children especially as "other". It also indicates, however, the limited understanding these majority ethnic children had of racism in contrast to their minority ethnic peers (including Irish Traveller children), all of whom were able to recount their own experiences of being racially abused for colour and/or culturally-based differences. The need for teachers to be sensitive to the dynamics of children's social world is stressed, as is the importance of developing clear procedures for the monitoring and tackling of racist incidents in schools. (Contains 2 tables, 1 figure, and 4 notes.)