In my last post, I tried to prove that science practicals were not the best way for students to learn new scientific content. I want to try and look at the generalised skills of enquiry and analysis that they supposedly promote – the ability to think scientifically.

First off it is important to note that there is a huge debate raging about “knowledge” and “skills.” It’s messy and complicated. Some easy initial reading can be found here and here (£).

Terminology aside though, the consistent picture from the field of cognitive science is that generic, transferable skills cannot be taught. What I mean by that is that if I spend an hour in chemistry teaching my students how to analyse a particular passage or question, their skills of analysis in history, geography or English will not be improved. Generic and transferable analytic, evaluative or descriptive skills cannot be improved in a general sense. These “higher order” or “critical” transferable thinking skills do not exist. Even the holy grail of education – general creativity – does not exist.

Instead, the weight of educational research supports a different conclusion, one I mentioned in Part 2. Your ability to think about a particular topic depends in large part not on your general thinking skills, but upon your depth of knowledge of the thing you are thinking about – your domain-specific knowledge. Almost every experiment over the last 100 years has proved the same thing, whether it is conducted with accountants, grand chess masters or air traffic controllers. The skills they utilise in their own field do not transfer to other fields.

Let’s take a basic example. Sir Ken Robinson, saviour of schools, has this video about “divergent thinking.” In it, he poses the question “How many uses for a paperclip can you think of?”

He says that people who are “good at” divergent thinking can come up with a couple of hundred answers. They do this by saying things like “well can it be 200ft tall and made of rubber?” These people are classified as “geniuses at divergent thinking.” It turns out that 98% of kindergarten students reached this level. However, as they grew older these numbers diminished rapidly. This is considered to be a Bad Thing.

The problem is, it isn’t a Bad Thing. In fact, it’s a Good Thing. I can’t remember for the life of me where I read this, but the whole point of growing up is that you become more efficient and effective at performing tasks. Can you imagine if every time you sat down to dinner you picked up your fork and started thinking about all the hundreds of things you could use it for? You would starve to death and win a Darwin Award. That’s how children act. It’s why they play with everything they can get their hands on. And it’s why they need parents standing over them reminding them that a road is a thing for cars to travel on, not a really exciting imaginary swimming pool. Sporadically and without focus, they gather masses of experience to prepare themselves for life – what is safe and what is not safe – without their parents standing over them.

I have a further but related objection. I can think of two good uses for paper clips: clipping paper and springing the manual opening mechanism on CD drives. But other than that, for the life of me, I cannot think of anything I could use a paper clip for which does not already have something specifically designed for that purpose. Coming up with new uses doesn’t make you a divergent or lateral thinker, it makes you inefficient. If every time your hair dryer blew a fuse you tried to open the plug with a paperclip you wouldn’t have any time to, you know, eat. And then you would die. Just use a screwdriver!

But here is the real nugget. I know that paperclips are great for opening CD drives. But I probably wouldn’t consider myself particularly creative. Let’s take someone who definitely was creative. Let’s take Picasso. If I gave Picasso a paperclip would he say that he can use it to open a CD drive? Probably not. Even if I gave him a laptop would he work out that the tiny hole on the drive can only be opened with a paperclip? I doubt it. I imagine someone would probably have to tell him.

So to bring this back to science practicals. Let’s take an experiment where students mix different metals with acid, see which one bubbles the most, and rank the metals by their reactivity (how much they bubble). I did this experiment with my year 10 triple scientists this week. They found that the iron bubbled more than the zinc and was therefore more reactive. However, when they looked in their textbooks they saw that actually iron is less reactive than zinc. So why the difference? The most able scientist in the class was the first to ask me. He had given it a really good think but was coming up empty. I held the two pieces of metal next to each other and asked him what the difference was. He realised that they were different shapes – the iron was in wool form and the zinc was just a small nugget. Why should that make a difference? He didn’t know.

This student hasn’t learnt about rates of reaction yet. When he does he will learn that the surface area and shape of a material affects the speed at which it reacts. Once he does though, he would have realised much earlier on that actually the experiment we did this week was an unfair test, one in which multiple variables had not been controlled. His ability to identify these variables, or think scientifically, would have been improved. Not by him having done lots of other, unrelated experiments, but simply by knowing more stuff.

The next section will be about motivation and engagement, then I want to try and write something about preparing students for University.

Introduction: are we wasting our time? – part 1

The Cognitive Science of Practical Science – part 2

Thinking Scientifically – part 3

Do Science Practicals Boost Engagement? – part 4

Mary the Super Scientists – part 5

Teaching Practical Skills: If You Aren’t A Science Teacher, Leave Me Alone – part 6

Conclusion – part 7