This article examines the development of pedagogical knowledge and the formation of a didactic repertoire by pre-service teachers during teaching internships. It highlights the complexity of teaching practices, underscoring the significance of interaction, reflection, and experimentation in learning. Employing an ethnographic approach, the study delves into the dynamics between instructors and students to understand how the latter access practical and theoretical knowledge. The research utilizes projective narratives and self-observations to explore decision-making processes and the construction of personal practical knowledge within teacher training.