I recently watched and very much enjoyed this webchat between Oliver Lovell and Tom Sherrington. Lovell has recently written Sweller’s Cognitive Load Theory in Action, and Sherrington was interviewing him about it.
About 24 minutes in, Sherrington asks Lovell for “the main thing that teachers should do.” Lovell gives three things to avoid:
- Redundancy: cut out anything you don’t need. Anything redundant wastes precious working memory.
- Transience: for example, when running through a powerpoint, remember that the information is transient. It’s on slide one, but not slide two, three or four, but you still need the class to remember it, and that takes up working memory.
- Split attention: “information that must be combined, should be together in space and time.” Sort of a development of transience, I think.
Good stuff. Eminently and evidently sensible. So much so that Sherrington describes it, in a much more complimentary way than will come across on the page, as “Obvious, obvious, obvious.” He’s not belittling Lovell’s ideas. Rather, he is praising Lovell for his research-based clarity of thought and expression, and the obvious link between Cognitive Load Theory and Lovell’s practice. Nice.
I agree. I think Lovell’s suggestions are excellent. They are indeed obvious, once you come to think about them. What’s more, they just feel right.
The problem is that other things just feel right too, even when they’re wrong. Way back in 2008 the great Daniel Willingham, of whom I am an enormous fan (ask any of my classes), made a video called Learning Styles Don’t Exist. I’m sure that somewhere he once apologised for its “garage band quality”, which I rather liked, but the information is good and, as it happens, I buy it. Of particular interest, though, is that Willingham himself says that the learning styles theory, specifically the visual/auditory/kinaesthetic variety, “seems to make a lot of sense.” He even asks, “Why does it seem so right?”
He says there are three reasons:
- Because everyone believes it;
- Because something close to the theory is right;
- Because of confirmation bias (though he doesn’t use that term).
I think you could apply a lot of that to CLT, or rather to the way CLT is being used in the classroom. As Sherrington implies, Lovell’s suggestions “seem to make a lot sense,” and so they do. It may even be that they are sensible because they derive from CLT. But it may not.
I recently highlighted some doubts about the robustness of the methodology underpinning CLT experiments. (To save you a read: it’s not clear that we can measure cognitive load very well, which to me begs the question of whether we should be building theories of education on it.) Be that as it may, once you’re into cognitive load, you see it everywhere and it explains everything.
Your students wrote rubbish essays? You probably overloaded their working memory with new information. They can’t factorise? I expect you didn’t do enough worked examples. They forgot to bring their swimming kit? Well, that was one of four messages you gave out in form time yesterday.
Alternatively, perhaps you explained the essay really badly. Maybe, during your factorising lesson, they were all thinking about inter-form football later on. Perhaps they were hungry in form time, or focused on the latest gossip. The CLT explanation might feel right, but is it? How can you know?
Ironically, perhaps, Willingham’s VAK video makes a similar point. He imagines a teacher trying to explain the structure of the atom, but “it’s not really clicking. Finally, you say, ‘Picture the solar system. The nucleus of the atom is like the Sun, and the electrons are like the planets spinning round it.’ The student understands and you think, ‘Aha! The student must be a visual learner.’ But maybe that was just a good analogy that would have helped any student, or maybe the student needed just one more example for the idea to click. Why the student understood at that point is actually ambiguous.” (My emphasis.)
The same could be said of CLT. You’ve read about it, maybe been to talk or a webinar. So you strip down your explanations, use worked examples, rid your slides of diversions and – ta-dah! – your students ace the test. Cause and effect? Maybe. Probably your teaching, free of frills and frippery, was clearer and sharper, and thus more likely to produce the desired results. But can you be sure that was due to your adherence to CLT? Or was it just that you thought harder about how you were going to explain things? As Willingham says, “if you already believe, ambiguous situations are interpreted as consistent.”
I’ve written before about the the seduction of quick clarity: the danger that we alight on something that seems to make logical and accessible sense of a difficult and nuanced issue – teaching, for example. CLT certainly seems logical and can be made accessible: witness this by Adam Boxer. That doesn’t make it right – VAK wasn’t, after all – but it will still lead us to teach in particular ways and, perhaps damagingly, not in others. That’s for next time, though.