Using a post-structural, interpretive perspective, we studied children's humour in a grade-1 and -2 classroom. In this article, we report our observations of two boys who took on the role of "class clown." The boys used humour to negotiate power, which we defined as participation in discourse, taking on the role of class clowns and playing these roles, based on the context of their actions and responses of their peers and teachers. They were also defined by their roles because their teachers and peers came to expect certain actions from them. These two boys contributed to classroom discursive practices and also limited the classroom discourse.