School makes you smarter
In the most popular TED talk of all time, Sir Ken Robinson makes the case that schools kill creativity. The evidence for this claim is weak. However, the evidence that schools make you smarter is robust and this has important consequences for education and the economy.
The holy grail of education is to find a way to increase people’s general abilities and yet this is hard to do because the things we learn tend to be locked to the context in which we learn them.
Imagine, for instance, that you teach students about the scientific idea of a controlled experiment. You ask them to consider the example of a flu drug that apparently makes patients better after a few days. Then you suggest that these patients may have felt better after a few days regardless of whether they had taken the drug or not, and so you need a control group to compare them with; a group of patients with the flu who didn’t take the drug. Your students may well be able to recall this example and explain the logic behind it quite lucidly. However, when you present them with an example set in a different context, such as an attempt to test the effect of diet on weight, they may well be mystified. They may even struggle to apply the idea to the example of a test of a different kind of drug.
This is known as the, ‘problem of transfer’ and you can imagine the result. For any given concept, if teachers know that only a small number of examples are likely to occur on an exam then they will teach these examples. Exam results will then not indicate what they are supposed to indicate and employers will be left scratching their heads, wondering why their new employees seem to be lacking the skills that, on paper, they possess.
The traditional way to tackle the problem of transfer is slow: You have to teach numerous examples, cycling back and forth between the abstract principle and different contexts. And you have to do it for every concept that students come across. This needs to be supported by high quality exams that are set by a third-party and are not predictable.
Wouldn’t it be better if we could short-cut this process and teach general reasoning skills? This is the idea behind attempts to teach ‘critical thinking’. Unfortunately, the evidence is lacking that we can teach general skills in this way. Instead, critical thinking seems to be something that largely emerges from sufficient knowledge of a topic. The same individual can think critically in one context and fail to do so in another.
The same is true for the ‘creativity’ prized by Sir Ken Robinson and others and the key here lies in Robinson’s own definition of creativity; ‘the process of having original ideas that have value.’ Anyone can have an original idea. Your dad could doodle something on a piece of paper that nobody has ever doodled before. But in order for it to have value, it probably needs to relate to previous concepts in the field, if for no other reason than to overturn them. Before you can rewrite the rules of business or music or quantitative biology, you probably need to know something about what those rules are.
So perhaps the goal of a general increase in people’s abilities is a hopeless one. Perhaps all we can achieve is to grow knowledge in specific areas. That’s a pessimistic outlook and one that is, thankfully, at odds with the evidence. It turns out that school does seem to make you smarter in a general sense.
We have known for a long time that more schooling is associated with greater general intelligence but it has been hard to untangle cause and effect. For instance, people with higher general intelligence might choose to stay at school for longer and go to university.
In a new piece of research, academics from Scotland and the US examined a range of studies that looked at the effect of the amount of schooling on general intelligence.
These studies either attempted to compare students with similar initial levels of general intelligence, or made use of ‘natural experiments’ such as when a region changes its school leaving age before a neighbouring region does, or when similar students sit either side of the cut-off date for school entry. The results suggest that, all other factors being equal, more schooling leads to greater general intelligence.
So how does school manage to do this? One hint comes from a study published last year of American college students. Researchers measured their critical thinking skills before and after taking various courses. The students’ ability to think critically increased but this was regardless of whether they had taken a specific critical thinking course or not.
Many psychologists view general intelligence as being made of two components; fluid intelligence and crystallised intelligence. Fluid intelligence is basically raw processing power; how many items your mind can attend to simultaneously. Despite many attempts to do so, the general consensus is that we have not yet found a way to increase people’s fluid intelligence.
Crystallised intelligence is essentially knowledge. It’s not just dates and names, however. Crystallised intelligence would include knowledge of useful principles and heuristics. It would also include knowledge such as, ‘I’ve seen something similar to this before.’ It is likely that this is how we solve many of the problems of everyday life; we compare them to past experience rather than working them out from scratch. It may be that school increases our crystallised intelligence and this doesn’t just make us smarter in particular subject areas but, over time, it also increases our general abilities.
It may be fashionable to point to a particular item in a school syllabus and ask, ‘What use is it to know quadratic equations? When are they used in real life? Why don’t we teach students to think critically instead?’ However, this would be a mistake. Although a slow and laborious process, we know how to teach content and it is learning this content that seems to be the one clear way to make students smarter.