Train Pupils To Recall Knowledge Efficiently And You’ll Be Surprised How Much ‘Cleverer’ They Become

Despite all the myths surrounding it, of all the different characteristics of the human brain, intelligence is a good candidate for being the most well researched and best understood. So, what is it? And ultimately – can we make children cleverer? The answer is, it depends.

The psychologist Raymond B Cattell describes ‘fluid’ and ‘crystallised’  intelligence. Fluid intelligence is usually defined as the ability to reason and solve problems, whereas crystallised intelligence is the ability to access and utilise information stored in long-term memory.

It turns out that while they’re not the same thing, fluid intelligence correlates surprisingly well with working memory capacity. Although everyone’s working memory is fragile, there’s no doubt that some people have greater capacities than others.

This confers a real advantage – sadly, though, despite the claims of various brain-training gurus, it doesn’t actually appear possible to increase working memory capacity: what you get is what you’ve got.

The advantage of information

So, what about crystallised intelligence?

This is a much more profitable avenue of enquiry.

If part of the measure of general intelligence is the ability to access items stored in long-term memory, then the good news is that for all practical purposes there’s no real limit to the amount of stuff you can cram into your brain.

Of course, what we know is subject to forgetting, but with practice we can improve our long-term stores of knowledge quite considerably.

Other good news is that the ability to remember doesn’t seem to rely on fluid intelligence. No matter how poor you are at reasoning or problem solving, you can still commit facts to long-term memory. And, the more you remember, the easier it becomes to remember additional items of knowledge.

The real benefits become clear when we understand that by improving crystallised intelligence we can ‘hack’ our fluid intelligence.

That is to say, we can use what we’ve stored in long-term memory to compensate for deficits in working memory.

When information is stored in long-term memory it gets organised into schemas – interconnected webs – which mean that when we retrieve one item we also bring with it all the information it’s connected to.

There are two ways we can cheat the limitations of working memory:

Stop focusing on skills

Teachers invest far too much effort trying (and failing) to improve fluid intelligence by drilling students in ‘skills’ like essay writing.

Unfortunately, writing essays isn’t really a skill that we ever automatise – in order to write thoughtfully we have to think. And, no matter how clever you are, you can only think about what you know.

Worse, there are still schools and teachers who see themselves as best serving the needs of children and society by concentrating on generic skills like creativity, collaboration and communication.

These skills are for the most part dependent on fluid intelligence and if we take this approach we guarantee that those with greater working memory capacities will do well and those who don’t will struggle and often fail.

If instead teachers prioritised encoding and retrieving knowledge then all children would see an increase in crystallised intelligence.

In this system, the entire bell curve is more likely to move to the right. Admittedly those with higher fluid intelligence would still do better, but there wouldn’t the long tail of underachievement we currently have. All students would get cleverer as they passed through the system.

David Didau is an independent education consultant and writer. He blogs at learningspy.co.uk, and is the author of several books, including What If Everything You Know About Education is Wrong? and The Secret of Literacy.

His new book, What Every Teacher Needs to Know About Psychology, has been co-authored with Nick Rose and is available now. You can follow him at @LearningSpy

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