ABSTRACT
Language is central to human culture, and is widely recognised as a key tool in learning. Teaching relies heavily on the use of language (Edwards & Mercer, 1987). Analysis of science teaching shows how skilled teachers use language as a nuanced tool to persuade students of the viability of the scientific accounts (Lemke, 1990; Ogborn, Kress, Martins, & McGillicuddy, 1996). Much of this language is spoken (or written), but verbal communication is just one part of a broader range of symbolic language (gestures, formulae, etc.) used in science teaching (Kress, Jewitt, Ogborn, & Tsatsarelis, 2001).
