The main goal of this research was to investigate how Natural Sciences teachers conceive interdisciplinarity and how they undertake interdisciplinary work on a common subject: the greenhouse effect. Based on qualitative research (questionnaires) the student teachers from an in-service project expressed their initial conceptions on the subject. Data collected and analyzed showed the following outcomes: teachers interviewed have only simple conceptions on interdisciplinarity and demonstrate a confusion between this concept and multidisciplinarity. They find it possible to work with the concept of the greenhouse effect in an interdisciplinary way, but they do not point out appropriate ways to approach it, due to their conceptual inadequacy.
interdisciplinarity; teachers' conceptions; Natural Sciences; High School Teaching; formation in service