In higher education, there is an increasing interest in student interaction in the form of peer learning. In the literature, peer learning is mainly presented as a pedagogical tool used to promote curriculum learning. This article is based on observations of peer learning that expand beyond learning of the curriculum. It particularly addresses the phenomenon of students creating niches for peer interaction and learning. There is an additional type of learning in higher education that can be called peer-mediated learning. In the peer-mediated niches, students learn to become students, and they are free to agree or disagree with the course content in a way that they cannot express in their assignments and examination papers. The article discusses peer-mediated learning from the perspective of activity theory and the notion of the zone of proximal development. It finds that the conventional understanding of the zone of proximal development does not explain peer-mediated learning.