This paper discusses the application of Karl Maton's notion of 'semantic waves' to the teaching of geography at the post-16 phase (A-level) in England. Drawing on evidence generated through a 2-year close-to-practice case study, it illustrates its potential as a scaffold in two ways. Firstly, one that can help teachers face both ways: Towards their subject discipline, to see it in more naïve forms, and towards their novice students, to make that form explicit and thus accessible to them. Such a deliberative or hermeneutic orientation stands in sharp contrast to the atomistic mode of the technicist orientation to knowledge dominant in English education. Secondly, as a scaffold that can provide a visual language for students which makes explicit the implicit relationship between different components of an essay, and in this sense, helps scaffold for a more relational mode of thinking about the geography itself. Interviews with students suggested semantic waves was: (i) a practical but not a prescriptive tool, (ii) a framework that could extend their thinking and (iii) a scaffold that connects knowledge with essay writing. It appeared to be a useful tool to bring the geographical knowledge and its complexity to the fore by aiding metacognitive thought.