Who was and what was the work of Lev Vygotsky? Who is and what is the work of Bruno Suchaut? Who is and what is the work of Howard Becker? Who is and what is the work of Jean-Paul Payet? Who and what is the work of Gérard Sensevy? Who is and what has been the work of Guy Brousseau?... What is a "professional gesture"? What does "joint attention" mean? What is "real work"? Does the question of "deviance" arise in schools? Do teachers do "dirty work"? What do we mean by "devolution"? What is a "narrative"? How do teachers read Gilles Brougère? Etc.