Understanding the challenges of the entrance of art in today’s schools raises questions of what teachers say, think, and do when they engage in art practices. A proposal identifying our problem, inspired by the theory of estates and the themes of justification, can introduce the plurality of worlds of our time in the heart of the apparent consensus concerning art that educates. This paper presents a study conducted in seven classes with an artistic or cultural project in French primary schools, with about thirty students each, in each of which observations of situations and teacher interviews were conducted. This article outlines the most representative of our case studies. Analyses revealed the existence of a plurality of values and principles of justice in effective educational practices.