La Cité des geometries de Maubeuges, in collaboration with the Tunis Science City, organized a pedagogical day at Al khawarezmi auditorium , including two lectures: one  by Valerio Vassallo and the other one by François Recher, both  professors of mathematics at Université de Lille1. The first lecture  entitled “Between arts and mathematics, there is a soap bubble”; the second one “A paver knowing how to pave” .