I think what I try to get students to see is that we use models and you use a model, while it works. Then when it doesn’t work you develop a more sophisticated model, and what we’re doing now is developing a more sophisticated model of the structure of the atom, of bonding between atoms. So they find that difficult, the fact that you’re putting aside the model you used previously and developing a more sophisticated one. I think that’s something, it just knocks their confidence a bit.
So my approach to teaching is that I want students to be actively engaged with the material throughout the lectures, all the tutorials, all the workshops or whatever, and so I’m not giving didactic lectures, I’m not using lots of PowerPoint slides. I’m giving them information. I’m describing things to them, but then I give them lots of examples and lots of things to do, lots of activities to do.
So into the lectures I put kind of ad breaks, I suppose, short 'meet the scientist' breaks. So we would have a photograph and fun facts about a scientist and various places we would have a stop, and I have told them that all of that information wasn't on the exam, so they knew that they could stop and just take a breather and then pick back up on the chemistry afterwards. So that, I think helped, especially the ones that were just finding it all a bit kind of overwhelming.
Tell them to go to Spotlight and get some toothpicks and some polystyrene balls. The problem then is you don’t have the correct angles, but usually it’s enough to get it out of their head.
We do Lewis Structures and then we do molecular orbital theory, and it's theory after theory and they say, 'Why do we have to do this theory and this theory and that theory?' You need to say 'Well, because they're all slightly different interpretations because we don't actually know how it is. This is model one and this is model two.'
A topic like this is quite theoretical and if you approach it in a very didactic way, it can be very dry. It’s undoubtedly quite abstract, and if you present it in a fairly traditional way it’s even more so. Try to engage students with it, and get them to think and discuss and use different approaches. Coming at it from different ways helps to bring it alive a bit.
An analogy in quantisation of energy states takes advantage of the fact that in many lecture theatres there are shallow steps going down to the front. Think of a ball rolling down the steps. It can't stop halfway down the steps. It seems like a really simplistic way of thinking of it, but in terms of analogy it works really well.