Consistency of children's use of science conceptions: problems with the notion of "conceptual change"

A study of primary school children's explanations of a range of phenomena concerning air pressure revealed considerable fluidity in their use of conceptions. A measure of consistency was developed and applied to children's written and oral explanations in a range of contexts. While the results showed a general trend with age toward more abstract, 'generalizable' conceptions, the notion of parsimony was found to be problematic on a number of levels. Children do not apply a single conception to a phenomenon, but rather operate with multiple conceptions in their explanations, complicating the whole notion of consistency. Moreover, as they develop and apply more advanced conceptions, children inevitably display temporary reductions in consistency. These findings suggest a rather more complex model of conceptual advance than implied in the literature on 'conceptual change'.