School is not only a place where instituted knowledge is taught, it is also a place where things are not explicit and taught as such. The description of a start-of-term ritual in a primary school, a study of the way rules are established in the first grade and an ethnographic observation of rituals in mathematics lessons in fourth and fifth grade classes provide an opportunity to analyse these different functions of the rituals and to study their role in organising teaching situations, the conditions under which knowledge is disseminated and, more broadly, the establishment of the school order in primary schools.