A study is presented in which the aim was to promote school coexistence in a group of 4th grade of primary education, through an intervention project developed from the subject of Civic and Ethical Formation. It is a study with a qualitative approach and an action-research methodology, as it values teaching as a reflective activity aimed at improving the practice of teachers in the classroom. The participants are 27 students and an eighth semester teacher training student doing his professional practice in a primary school in Mexico. The intervention project addressed the issue of coexistence among students, generating a better atmosphere of cooperation and harmony, which is necessary to foster a climate of trust in the classroom and, consequently, of learning. Various didactic strategies were implemented, emphasising teamwork, promoting dialogue and cooperative learning.