Céline Piquée, Bruno Suchaut. An extra teacher in the classroom: what effects on progression of children in "cycle 3”? (cycle 3 = last three years of elementary school) To try and reduce school achievement discrepancies at primary school, an original set of actions has been conceived and implemented in the area of Haute Marne. The idea is to provide primary schools in Education Priority Areas with an extra teacher, thus making it possible for the "cycle 3” teachers to occasionally split up the class into groups in order to give special attention to underachieving pupils. This article accounts for the results of an evaluation of the effects of this set of actions on the progression of children in French and maths in "cycle 3”. The plan of actions, with the present lay out at least, doesn’t seem to meet the set targets: the underachieving children dealt with in smaller groups progress no faster than the children with comparable characteristics but taught in traditional school environments.