The present research is inserted in the context of Cultural Diversity and Education studies and intends to focus on the changing process which the Colégio Stella Maris, in Rio de Janeiro has been through these last years. This teaching institution, a traditional and confessional school, educated Rio de Janeiro´s high and middle classes for 65 years. In 2000, the school experienced a transforming process, due to different circumstances and also to a choice made by the religious congregation responsible for the school. It began to assist primarily the low class population living in the neighborhood, the inhabitants of the Vidigal favela. The main purpose of this investigation was to identify the implications of this clientele change to the school itself and the differences in the teachers´ behaviour and in their pedagogical practices, not only theoretically but also when facing daily life problems. The strategies used in the field research were: document analysis, observation and interviews with the main subjects. In the data analysis, special attention was given to the implications of the studied questions to the social and cultural diversity in the pedagogical dynamic of the educational institution.