A Residue of Physics

Six months ago, I was helping English trainees write a knowledge organiser for The Strange Case of Dr Jekyll and Mr Hyde. We were struggling with the knowledge that the students would need for the Jekyll and Hyde unit, but which we didn’t care too much about long term, and the knowledge that we wanted the learners to carry for life – something less tangible, but more important. Not the sort of knowledge of quizzes and knowledge organisers.

In 2012, Christine Counsell wrote about two types of knowledge for history: fingertip-knowledge and residue (see here p65). In history, fingertip knowledge is the knowledge learners need at their fingertips to follow an enquiry in history in class – it is detailed and ephemeral. The residue is the rich, lifelong knowledge which remains when the fingertip knowledge fades away.

We were struggling with this concept in English; fingertip knowledge is easy to put into knowledge organisers and assess in quizzes, but residue is different.

How do you assess the residue of learning? How do you even know what questions to ask? I don’t know, but I think I know it when I see it.

This left me wondering whether fingertip knowledge and residue was a useful concept for physics. On the face of it, I want everything learnt in science class to be fingertip knowledge. It isn’t like English or history: knowing the first 20 elements of the periodic table needs to stay fingertip; knowing that the sum of current entering a junction equals the sum of currents leaving it needs to stay fingertip.

My first thought was that all physics knowledge needs to be fingertip all the time. Not knowledge that is an inch deep and a mile wide either, but an interconnected web of knowledge (as described by Rosalind Walker here and here).

But what happens after the lessons have stopped (presumably the real reason we teach physics to all to GCSE). At the pub last week, two teacher acquaintances and I thought we’d explore their physics residue. Neither had studied physics since their GCSEs.

I asked them what would happen if an astronaut on the moon released a hammer and feather at the same time.

Both were able to reproduce a correct and well worded description and explanation with some correct terminology. Both claimed that they didn’t know it and had to reason it out. When pushed, one felt that he had picked it up from reading and tv. This is residual knowledge – it’s the physics knowledge of an educated, literate person. 

When I asked a bright year 8 girl the same question, she was unable to give such a good explanation, even though she has studied it at primary school and in year 7.

This suggests that it takes time and repeat exposure to build this residual knowledge. We can’t track where it was learnt and how it was developed. It is different in nature to the knowledge of knowledge organisers and quizzes.

If residual knowledge is important, perhaps we ought to work out how to track its development and assess it. I’d like to think we build the initial schemata, but I think we ought to be making sure.

@benrogeredu