We need to change the way we teach science (part 2)

In response to my last post on science teaching, my father asked for some examples to clarify the type of science teaching I had in mind. Well, for those that asked, and those that did not, below are a few examples of the kind of science...let's call them...'experiences' I have in mind. The guiding principal for all these experiences is that, to make a science experience meaningful, you need to be answering a question the students actually care about.

 

You can start giving kids science experiences from the very beginning. Actually, as soon as their about six months old (probably earlier for some), kids are doing science. They make hypotheses, they test them and then they learn from the results. Don't believe me? How about learning to speak? Babies make noises. I assume initially by accident they find that some noises elicit a response from people around them. They hypothesise that these noises will elicit a response from Mum and/or Dad every time they make them. Some noises do. Some noises consistently elicit a very big and pleasurable response from Mum and/or Dad. Through science, babies learn that some noises are good for getting people to respond in certain ways, so they keep making these noises. I'm not saying that babies are conscious of this at all. I am just saying that kids are hardwired for science from the beginning, so most, if not all, will be enthusiastic for well-crafted science experiences.

 

What about with toddlers? What science experiences are appropriate for them? I stumbled across a fun one with my three-year-old a few years back. He had a 'magnet wand', which is basically a fairly strong magnet encased in a plastic handle. He enjoyed sticking it to the fridge and oven and the washing machine. He was wondering one day why the wand stuck to things. I jumped on this opportunity and suggested that there could be a few reasons, since the things he had been sticking it to all had common features. Together we came up with two hypotheses: H1 the magnet wand sticks to things that are white; H2 the magnet wand sticks to things that are metal. Then we went around the house finding metal things of different colours and concluded (obviously!) that the wand stuck to things that were metal. I think simple experiences like this can start kids thinking scientifically. They will start to see that the world is comprehensible and ordered and that, through science, we can understand and manipulate the world.

 

What about 6- to 12-year-olds? There are so many ways you can introduce science into a child's life to answer questions that really matter to a child, such as: what is the best type of sand for sandcastles? Or what is the best chocolate chip recipe? Or what is the best method to clean up the baking soda/vinegar volcano mess that just frothed all over the carpet? And how can I get it clean without Mum or Dad ever knowing it was there?

 

I hope you can see the point I'm making, but what about for high school kids and college students? How can we give older kids or teens meaningful science experiences? You might ask a very simple question, to which your students may know the answer, like why do plants get heavier? Your students might know a bit about photosynthesis, but few of them will have seen experimental evidence for it. So, you could ask, where does plants’ extra mass come from? Are plants taking up something from the soil or air or light or some combination of all three? You could then ask students to come up with methods of testing these four hypotheses. For example, you could grow some plants in the dark and some in the light and see which ones get heavier. You could grow plants in different gaseous environments. You could weigh the soil before you grow a plant in it and then again after the plant is grown to maturity (after removing the plant from the soil, of course!). Thinking about photosynthesis in this way is not only going to help students develop their scientific skills, but it will also teach photosynthesis in a way that sticks.

 

And what about at university? The approach that I have taken with my recent lab redesign is to give the students several tools they could use for conducting an experiment and then letting them decide which tool they want to use. The goal of the lab is to separate proteins in a mixture using chromatography. The students will be supplied with two types of resin and three buffers at different pH values, but it is up to them which resin to use and which order to add the buffers. This forces students to really grapple with the concept of separating proteins based upon differing pI values.

 

I could go on, but I think I'm just multiplying examples at this point.

We need to change the way we teach science

Recently I have been involved in re-designing a university laboratory course. The process got me thinking about the philosophy behind the way we teach science. And I have come to the conclusion that we've got it wrong. Well, largely wrong.

Let's start from the beginning. The way I was exposed to science as a child was through museum exhibits, books, magazines and science live shows. I suspect your experience of the practical side of science was similar. It was great seeing how vinegar and baking soda frothed and bubbled like a volcano. It was cool seeing the catalytic effect of cigarette ash when trying to burn a sugar cube. I loved seeing a flower smashed into hundreds of pieces after being dipped in liquid nitrogen. These cool demonstrations of science gradually became more complex as I progressed through high school and into college and university. But even at university, the principle was still much the same. The underlying principle throughout all my science education was to understand certain concepts and memorise certain facts. The way this usually worked (even at the university level) was that we were taught something in lectures and then the labs provided practical experience of the concepts being taught. My science education was probably somewhat unique, since I was home schooled, but I think that science education in principle is largely the same throughout the Western world: science is taught as concepts to be understood and facts to be memorised.

Granted, science concepts and facts need to be taught and understood and practical demonstrations/experiences are great for re-enforcing concepts taught in class. But science practical classes are rarely true experiments. They may be described as experiments but there is no element of uncertainty; there is no new knowledge gained. There is just re-enforcement of ideas to which students have already been exposed. Science practical classes are largely recipes that are followed to give an expected outcome. And if you don't get the expected outcome, then you must have done something wrong.

I propose a complete re-imagining of science education. From the very beginning of primary school to the very end of university, we need to focus more on the process of science. Yes, we need to teach students as much of the body of scientific knowledge as they can take in, but more importantly we need to teach students about the process of generating a hypothesis, designing and performing an experiment to test the hypothesis and comparing the experimental result to the hypothesis. One way we could do this is through designing practical classes where failing to get the desired result does not mean 'failing' the lab class. We need to give students the mental framework they need to be able to ask intelligent questions and generate meaningful experiments, provide the resources for them to conduct these experiment, and then give them the freedom to conduct their experiments, even if we know that they won't all work.

That's how we create good scientists.