Several authors question that the preparation of teachers to effectively manage challenging behaviors in the classroom is insufficient. To support the success of students with behavioral difficulties, it is essential to develop models of training that meet the needs of teachers. This article presents the inservice training program of classroom management, the Programme de formation à la gestion positive des situations de classe (GPS), specially designed for first- and second-grade teachers. It aims to develop professional skills of teachers in classroom management and challenging behaviors. The teaching formulas are proposed to support the development of self-efficacy beliefs among teachers to promote the implementation of educational practices to prevent and deal effectively with difficult behaviors in the classroom.