It is suggested that the contribution of history and philosophy of science (HPS) to science education can be enhanced through a consideration of scientific models which are relevant to major sectors of the curriculum. The possibilities for so doing are considered through the discussion of six assertions. A way of characterizing such models, based on the work of Lakatos (1970, 1978), is outlined and applied to a typically important sector, that of the nature of the atom. An analysis of the way that the curriculum for 14-16 year olds and typical textbooks in Brazil and the UK treat historical models of the atom is given. The use of 'hybrid' models was identified in those treatments. Hybrid models, by their very nature as composites drawn from several distinct historical models, do not allow the history and philosophy of science to make a full contribution to science education. They do this by denying the role of distinct models in the history of science and of the role of progression between these models in the philosophy of science. The consequences for the teaching of science of an appropriate treatment of historical models are outlined.