The aim of this study was to explore interaction in school activities of pupils with Down syndrome in mainstream schools to understand enabling conditions. Six ten year old pupils with Down syndrome were observed in their class, and interviewed. By applying qualitative methodology, we identified two main categories; equal and unequal interaction. Unequal interaction comprised patterns of peer supported and non-supported interaction. Peers’ support comprised modifying tasks, activities or their own behavior that enabled interaction with a less competent pupil. Peers support are discussed within the frames of inclusive schooling.