Ethnomethodology frames "culture" as enactments by participants that need to be studied in specific moments of interaction. The key research question is how people display in their talk particular understandings of culture with and for each other. In this paper we explore the way cultural categories are deployed by teachers and parents (of Chinese and Vietnamese heritage) to explain everyday events and decisions regarding the education of young children with special needs. We analyse how these categories were assembled during the talk, and what work was accomplished in deploying the cultural categories in this context. We found that in talking about specific actors or events, the parents' and professionals' reasoning could vary from using a general cultural category as accounting for attributes to situated and cautious reasoning about specific moments of everyday life. The participants' reasoning with cultural categories was nuanced and coherent, ambivalent and confused. This complex variability challenges the idealised subject imagined in so much social science research that seeks predictability and coherence. From a Bakhtinian perspective, the fact that our participants so regularly ruptured the achievement of such coherence might be regarded as a cause for celebration.