The predominant ideology among science educators is that hands-on experience is at the heart of science learning. As important as laboratory experience is thought to be, there has been little systematic analysis of just what can be achieved in the science lab. (Nersessian, 1989) A BRIEF HISTORICAL PERSPECTIVE Gee and Clackson (1992) trace some of the early history of practical work in universities and public education (including the development of guidebooks for conducting experiments in the home) and describe how early attempts to establish practical work in school science were frustrated by lack of facilities. They describe how this problem was overcome through various grants and government training initiatives. What is of more immediate interest in this article is the rationale employed in the promotion of practical work and the ways in which this has changed over time. Layton (1990) advances the view that practical work achieved prominence in the mid-nineteenth century because it afforded early pioneers of chemical education a justification of their subject in terms identical to those used for established subjects such as classics and mathematics -namely, that it teaches students how to learn. Subsequently, the argument was extended to biology and physics. However, Lock (1988) maintains that, in practice, practical work during this period 'filled a largely supportive role, that of confirming the theory that had already been taught', and that teacher demonstrations were much more widespread than individual experimentation by students. Downloaded by [University of Calgary] at 21:21 05 February 2015
86Derek HodsonIn the later years of the century, with the work of Meiklejohn and Armstrong, the rationale for practical work shifted from a concern with the promotion of generalized learning skills transferable to other areas of knowledge, to a justification in terms of training in scientific method (Brock, 1973; Layton, 1973;van Praagh, 1973; Jenkins, 1979;Waring, 1985). The thrust of Armstrong's approach, published in 1898 as The Heuristic Method of Teaching or The Art of Making Children Discover Things for Themselves, was doing science in order to understand science: 'once the methods of experimental investigation had been acquired in the workshop, these would be used continually in subsequent science lessons to 'find out' the information which others were forced to acquire by rote and demonstration' (Layton, 1990).Whether principally through changes in thinking in the psychology of learning (Brock, 1973) or in the philosophy of science (Jenkins, 1979), or because of a significant shift in the overarching goals of science education (Uzzell, 1978; Layton, 1973, 1990), Armstrong's heurism fell into disrepute and, with the impetus provided by the Thomson Report's (1918) declaration that too much time was wasted on repetitive individual practical work, attention switched back to teacher demonstration. The 1927 edition of the Board of Education's Handbook of Suggestions stressed the value of the demonstration experim...
