Finnish schools are famous for their egalitarian principles, but they face challenges related to pupils' equal opportunities and, more broadly, democratic schooling. In this article, we examine the lived consequences of a growing challenge, school segregation, using Basil Bernstein's concepts of inclusion and classification. Our analysis is based on ethnographic data produced in a lower secondary school located in a relatively disadvantaged residential area in the metropolitan area of Helsinki, Finland. First, we explore how the classification of pupils from different social class and ethnic backgrounds is present in the school. Second, we analyse how the strength of this classification affects pupils' right to inclusion. We conclude that weak boundaries between pupils, and thus weak classification, construct an inclusive school community. However, the different categories--social class, ethnicity or other--intersect, and the strength of their classification varies, which in turn affects pupils' peer relations and feelings of belonging.