PLACING THE HISTORY AND THE PHILOSOPHY OF SCIENCE ON

Recent research indicates that teachers conceive and orient his/her teaching depending (among others things) on his/her conceptions about both the nature of science and the construction of the scientific knowledge. This is an important educational issue because the image of science that is generally held by students consider science simply as a rhetoric of conclusions. Science teaching strategies designed in line with the principles of the “new philosophy of science”, e.g. emphasising the context of discovery of scientific ideas (and not simply the context of justification of those ideas), methodological pluralism and the human and social side of science (STS relationships), are usually ignored. Part of the problem lies in inadequated teacher education strategies. Thus the aim of this study was to design, to develop and to evaluate an innovative teacher education program exploring the History and the Philosophy of Science (HPS) in order to improve the teaching and learning of mass conservation in chemical reactions, a key curricular theme in Portuguese secondary teaching and also a relevant historical and cultural topic of study. The main hypothesis was that it is possible to develop in –service teacher education strategies based on the HPS to promote adequated epistemological perspectives o