This study aims to provide a better understanding of teachers' managing roles when using group work in the classroom. Building on Granström's 2 concepts of leadership and teachership, a more specific aim is to investigate teachers' managing roles when using group work and how teachers' presumptions affect the way in which they manage the pedagogical mode. The results show that teachers' managing roles influence teachers' willingness to use group work. Teachers may be unwilling to use group work based on their presumption that it teaches students only collaboration abilities and not subject knowledge. This may be a supplemental yet significant explanation as to why group work continues to decrease in classrooms.