I think to get the students to straight away mark for somebody else what they’ve just done and then to mark or take part in the marking of two other versions of the same thing is really powerful. So it’s not so much me directly finding out what they do and don’t understand but using methods by which they can diagnose for themselves. I haven’t got this, she has, or yep I have got most of that, she hasn’t, and I can see where she went wrong. Very powerful, very powerful indeed.
Expert Insights

It’s something that needs to be reinforced, it’s not that you taught it in this unit for three weeks, we are over it. It’s something that keeps coming back, and that you can possibly reintroduce it, with not much change to your teaching. Not every single time, but every now and then remind the students, ‘remember, you still have to think about stoichiometry and limiting reagents’. 
I think it’s really important that people mark assessments. Mark, and see what the students actually end up knowing. Because they can pretend to themselves that students have understood everything, but if they actually have to mark the exam papers, or the quizzes, or whatever it is, they actually are confronted with the students actual knowledge. I think that’s really influential. The second semester of teaching, when you think you’ve explained things well, and then 90% of the class have not got it, then it’s not the students fault at that point, it’s probably your fault. So I think that assessment is really important. Not only for the students, but also for the marker. I think you can learn a lot from marking. 
In the workshops, the workshop idea as we run them is that you are out and about and amongst the students all the time in those groups, seeing what’s going on in the groups, seeing how they’re answering their questions. They have set questions on sheets that they work through in groups and the groups of three just get one set. They’re all working on them together and you’re moving in and out and around among the groups and seeing how they’re going. In that circumstance you can quickly, having looked at three or four of your eight different groups, figure out where a particular issue would be and then that can be addressed on the board, it can be addressed with models or something like that. 
I think for a lot of people, before they started chemistry, especially if they haven't done any chemistry before, they've got no real understanding of the difference between macroscopic things and microscopic and atomic sized things. We all know how important that distinction is. 
So, just to make them do some work, and made them think about the ideas themselves. Talk amongst themselves about it. I think that just too much of me in the lecture just washes over them after five to 10 minutes. So they just need to have a break, think about the problem, do a couple of problems, talk amongst themselves... that seems to help, with both the variety of students in the class, but also just keeping them engaged. Keeping their attention. 
In the lab it comes out in a variety of ways. It comes out most commonly when the student gets to actually start doing their calculations and you ask them to relate that back to what they’ve actually physically measured. And when they start doing those sorts of things you realise there’s a bit of a misplaced idea here or a misconception that you can deal with there. 
When we’re teaching ideas in chemistry, I liken it to hacking your way through a forest. It’s all this detail.... and you can’t expect students to do the hard work of fighting your way through the forest or the jungle, unless they have a global view of where they’re going. What I mean by that is, the other factors that influence the way I teach intermolecular forces, is that I keep going back to applications in the real world. How is it that geckos can crawl up a wall, and almost sit on the ceiling without falling off? How is it they’re able to stay there with gluey legs or what? But the interactions between their feet and the ceiling are just, how could they maximise the attractions between the molecules in their feet, and the molecules in the ceiling? So what I’m trying to do all the time is to show applications, powerful, interesting, hopefully, and engaging applications of the ideas that are important. So, for students to engage and to feel, ‘well this is worth hacking my way through the jungle of detail to be able to understand it’, is to zoom out and show them how this topic relates to all of the other topics. It’s called scaffolding, and it’s a very, very important idea. So, the other factors are essentially the incredible number of other applications of this idea... that the power of an idea is its explanatory power, and when they can see just how important an idea is, in being able to explain all sorts of phenomena, they might be willing to care about it more. 
It’s continuous learning. I mean, what I used to try to say to students when I taught the acidbase stuff I’d say ‘look there are only about six types of problems and if you can solve one of them you can solve them all because they’re all the same.’ But what you’ve got to be able to do is look at the question and say to yourself ‘this is one of those types of questions therefore this is the way I should think about approaching it.’ So take the question, dissect it, decide what you’re being asked to do, decide what information you’re given, and then say ‘yeah that’s one of those types of questions, this is the way I should go about solving it.' If you can get that across to them, that it’s not a new universe every time you get a question, it’s simply a repeat universe of the same type of question... But many students tend to look at each problem as a new universe and start from the beginning again. Many students don’t see that there is a limited number of problems that can be asked on a certain topic. 
It was a revelation to me in second year when [one of the top professors] said to me, "Buy a model kit." And so now I tell all my students. 