Challenging able science learners through models and modelling
The four component ‘areas of science studied’ in the National Curriculum (NC) for England (DfEE 1999) for 5-to 14-year-olds – ‘scientific enquiry’ (Sc1), ‘life processes and living things’ (Sc2), ‘materials and their properties’ (Sc3), ‘physical processes’ (Sc4) – consist of a large number of facts, concepts, skills, and the relationships between them. It is therefore not surprising that students find ‘science’ difficult to learn (Osborne and Collins 2000). A close inspection of Sc2-4 showed that four ‘key ideas’ underlay the mandated content at Key Stage 3 (KS3, for 11-to 14 year-olds): ‘the particulate nature of matter’, ‘forces’, ‘energy’, ‘cells’ (Moore and Gilbert 1998). These four key ideas were adopted by the ‘National Strategy for Science at KS3’ and a fifth, ‘interdependence’, added (DfES 2002b). We are of the belief that ‘interdependence’ is not needed, the original four only being both necessary and sufficient for a full coverage of the curriculum. All the required facts, concepts, skills, in the three sections of the curriculum could be related to and explained with the use of one or more of these four key ideas. Furthermore, it was possible to identify the core features for each of those key ideas that was both ‘good enough’ for the purposes of the 11-14 curriculum and which would not be an impediment to more advanced study. Each set of core features of a key idea, where: ‘A model in science is a repre-
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produced for a specific purpose’ (Gilbert et al. model may have a range of ontological statuses. A scientific model is one currently in use at the cutting edge of research in a given field of enquiry. For energy this is currently a quantum mechanical equation. A historical model is one that was accepted by a community of scientists at one time but which has now been superseded for research purposes. For energy, one such model is composed of Joule’s mathematical equations based on the paddle-wheel experiment. A curriculum model is a simplified version of a scientific or historical model (usually the latter) that is included in the curriculum. For energy this could be either the ‘transfer’ or the ‘transformation’ model (Millar 2003) or a hybrid between them. These curriculum models are contenders for the right to represent energy in the science curriculum. A teaching model is an analogy that is created by the teacher (or students) in order to help in the understanding of a curriculum model. The ‘chain of students with arms linked’ is a teaching model for the ‘transfer’ curriculum model for energy.