In order to bring the student-teachers to enrich their observations and their respective practices in a way that takes into account the globality of the student's life, we will try to reflect on the following issues : through which pedagogical practices is happiness built in Primary School? How can the child's environment (climate, surroundings, classroom setting, learning and social environment, etc.) be incorporated into learning to promote well-being? Which posture does the teacher adopt? How can the student teachers make the pupils happy? What relationships between children, teachers , parents and other actors in and around the school contribute to this? In a comprehensive perspective, does project-based pedagogy, and in particular eTwinning, make it possible to encompass all these issues in order to promote happiness at school? How do different school systems enable children to reach their full potential? To this end, future school teachers who are either observing or in charge of pupils will exchange ideas with European students from ITEs participating in the Erasmus + programme