This article explores how teachers and learners in a Dutch as Second Language (L2) classroom in the Netherlands make sense of themselves, one another, and thereby of the diversity encountered in the class, through practices of categorisation and positioning regarding nationality, place, and culture. Categories raised during class gain meaning in interaction. Teachers and learners engage in positioning by assigning someone a relational location within or outside a respective group or category. It becomes clear that this way of social sense-making happens embedded in or alongside teaching and learning activities in the context of the L2 classroom where "using" and "learning" a language unfold as interconnected processes.