Why Ofsted’s account of disciplinary knowledge in science falls short
In my last blog, I attempted to highlight some of the problems that arise from disciplinary knowledge being treated as if it is just another category of substantive knowledge.
I used the example of history, perhaps unwisely, as the history subject community has already done a lot of work to ensure that the distinction between these two ways of thinking about knowledge is clear to teachers.
Unfortunately, in my experience, the same cannot be said for science. As an example, we may look at Ofsted’s research review for science, published in 2021. The table below categorises knowledge into substantive and disciplinary plus conceptual and procedural.
Here, examples of disciplinary knowledge are said to include things like “All measuring instruments, such as a thermometer, have a built-in degree of uncertainty,” and, “[know how to] Use a thermometer to measure the temperature of a solution.”
Disciplinary knowledge in science
What the author of Ofsted’s report is calling disciplinary knowledge looks a lot like substantive knowledge to me. Whether referring to propositions or procedures, all the examples given can be codified, memorised and practised or retrieved.
They are certainly not relational. They do not refer to the logical connections between concepts characteristic of scientific knowledge.
I’ve often heard science teachers discussing disciplinary knowledge as if it is equivalent to what used to be called How Science Works. This was a section of the specification in which students learned about concepts like accuracy and control variables.
These are hugely important ideas, but I don’t think they fully capture what is distinct about scientific knowledge, as opposed to historical or mathematical knowledge, for example.
I would argue that a better way of understanding disciplinary knowledge in science is by returning to the three-step process by which scientific knowledge develops. I wrote about this — and its limitations as a model — in an earlier blog.
Disciplinary knowledge is about knowing that scientists invent pictures with which they attempt to visualise the world. These are called models, and can be written about in the form of as if sentences.
It is about knowing that scientists deduce the consequences, should these pictures be true, in order to generate testable hypotheses. In other words, they use if … then … sentences to generate answers to the question: if my model is true, what would I expect to happen? These can be represented diagrammatically in a 2x2 grid, relating concrete cause and effect to abstract, hypothetical models.
And it is knowing that scientists must check whether their deductions are true by making measurements, measurements being an attempt to verify and quantify our senses with the aid of technology. In other words, we must generate data to test our hypotheses and interpret these data by using tools like graphs, all in the name of checking the extent to which our model can be thought of as true.
Disciplinary knowledge is abstract
All this is highly abstract; it is unlikely to be meaningful to students if they are told about it without some context. The best way for them to acquire such disciplinary knowledge is to be exposed to these logical connections systematically and repeatedly through multiple examples.
Thus, science teachers must be conscious of how they are laying out their diagrams in order to represent the deductive structure that governs the laws of science. They must draw students’ attention to the link between a phrase like as if and the metaphorical nature of scientific models. And every practical must be framed by the idea that measurements are the means by which scientists make decisions as to whether their ideas are true or false.
Contrast this with how disciplinary knowledge is often taught in science. In my experience, teachers typically assume they can cover all the ideas above in one lesson, on the history of atomic models. This would be a fair assumption, if we took disciplinary knowledge as just another category of things to be memorised. As we have seen, however, it’s not.
Students can only understand the significance of the models put forward by Dalton, Thomson, Rutherford and Bohr once they are familiar with the idea that scientists think in terms of visualisable images and have got into the habit of thinking deductively.
The ideas put forward by these thinkers should therefore only be introduced once we’ve given students lots of other, similar examples to look at and think about.
As a head of science, I had my department spend four lessons on the history of atomic models, situating it in Year 9. Before that, students had learned about the particle model (a simplified version of the kinetic theory of gases), Newton and Huygens’ models for the nature of light, Wegener’s model to explain continental drift, and others.
Reuniting curriculum and pedagogy
The point that has been running through this series of blogs is that we cannot consider either curriculum or pedagogy in isolation. I have argued that the tendency to do so is based on common-sense conceptions of knowledge as information and learning as the process by which information is stored in long-term memory.
My aim has not been to tell teachers to ignore categories like substantive and disciplinary knowledge. In fact, it has been the opposite. It has been to highlight that we must take these distinctions much more seriously if we are to build a curriculum that is pedagogic, i.e. accessible to our students.
Disciplinary knowledge is not just another category of the same stuff as substantive knowledge. It is different in kind. Taking this point seriously means thinking about how we can make the logical connections between concepts in our disciplines manifest to our students, something which can only be achieved by thinking carefully about our classroom practice.
We thus cannot separate the curriculum thinking from the pedagogical thinking. We cannot make choices about the what, then turn our attention to the how. The how must always inform the what, and vice versa.
The responses to my last blog, about history, suggested that the subject community comprising history teachers and academics has been thinking along these lines for a long time already. From my experience, the science subject community has not. This is why I am continuing to make my argument!
