The aim of this article is to present the results of the analysis of the learning concepts built by a public school teacher, throughout her academic preparation and her pedagogical practices. Using an ethnographic approach, the data were collected through observation of routine classroom practices (and their respective field diaries), recorded interviews and the teacher's own written reports. The results of the analysis suggested that this teacher has based her daily practices on genetic foundations, but she has also searched for behaviorist and humanist concepts which allowed her to have an effective practice.