Abstract Despite the hype and speculation about the role massively open online courses (MOOCs) may play in higher education, empirical research that explores the realities of interacting and learning in MOOCs is in its infancy. MOOCs have evolved from previous incarnations of online learning but are distinguished in their global reach and semi-synchronicity. Thus, it is important to understand the ways that learners from around the world interact in these settings. In this paper, we ask three questions: (1) What are the demographic characteristics of students that participate in MOOC discussion forums? (2) What are the discussion patterns that characterize their interactions? And (3) How does participation in discussion forums relate to students' final scores? Analysis of nearly 87,000 individuals from one MOOC reveals three key trends. First, forum participants tend to be young adults from the Western world. Secondly, these participants assemble and disperse as crowds, not communities, of learners. Finally, those that engage explicitly in the discussion forums are often higher-performing than those that do not, although the vast majority of forum participants receive “failing” marks. These findings have implications for the design and implementation of future MOOCs, and how they are conceptualised as part of higher education.