This is a case study with an ethnographic approach whose participant observations, individual and collective interviews as well as documental analysis were carried out in 2005/ 2006. The study encompasses space, time and subjects of a fifth grade group in a private school located in the Zona Sul of Rio de Janeiro. The school is well-reputed for its excellence in the educational community. It is a qualitative study that fits into a broader group of studies on the institution of the school, focusing more specifically on the organization of the curriculum and on school knowledge. To this end, it seeks to understand what happened in the context of an innovative pedagogical experiment started in 2003, when this particular school chose to work within the framework of investigative projects. Placing in the foreground, as foci for discussion, aspects relating to the tension between an integrated and a subject-based curriculum, to the constitution and/ or organization of school knowledge, to the limits and possibilities of the school as a space for the circulation and /or crossing of knowledge and culture(s) as well as to the characteristics of a pedagogic practice centered on projects, the study sought elements to support its analysis and interpretations in authors such as Fernando Hernandez, Pérez Gómez, Basil Bernstein, Jurjo Torres Santomé, Alice Casimiro Lopes, among others. The following questions arose and were the object of our reflection: the appropriation of different spaces as places for learning; the construction of students` autonomy and their role as protagonists; the impact of teachers` collective work; the preservation of subjects as a technology for curricular organization as well as the possibility of re- signifying their place in project-based work; the dialogue between different types of knowledge and the construction of school knowledge; the use of different media and investigative projects. Our goal is to offer a contribution towards a widening of the reflection and production of knowledge about schools as institutions that besides being aware of the needs characterizing the complexity of the XXI Century are also committed to the education of critical, creative, autonomous citizens, the subjects in the construction of a less dogmatic, more sympathetic world.