In this paper I present a workshop dedicated to in-service teachers about a special « Hungarian tradition » of mathematics education, focusing on Rózsa Péter’s Playing with infinity, a book popularising mathematics (Péter 1944/1961). The workshop in question is part of a three-days teacher training we offer every year since 2012 to secondary teachers of the Parisian region; the teacher training itself is related to an interdisciplinary research project in history of sciences and to a working group for teachers.First I will present this complex project which offers the context of my workshop. I will detail the construction of the workshop, and then I resume its content: the historical context of 20thcenturyHungarian mathematics education, and some elements of the analysis of Péter’s text. In the conclusion, I will talk about recent perspectives of the presented workshop, namely about the work ofa young French mathematics teacherinspired by the presented texts.