They're learning a new language as well as new concepts. There's a lot of vocabulary - terms like electrophile and nucleophile and many others. So it’s about learning the language, learning the curly arrow code that we use, and then starting to apply that in half a dozen different contexts.
Explain partial charges, with problems, then link this to bond polarity. Explain the differences in arrows 'language'. Draw organic structures as line structures and no stereochemistry (until you discuss that). Make stoichiometry explicit and link the structures to names to build on the concepts.
Re-teach electronegativity quickly because you don't necessarily trust the person who's taught before you. Make sure that it's reiterated, and then follow through to bond polarity and partial charges. Include all of that information first before going on to do reaction mechanisms. So the first thing to do is draw in partial charges to identify the electrophile and the nucleophile before going on to the next step. It's about doing examples all the way from first principles to build up those concepts.
Use model kits for third year pericyclic reactions: It's visual and it's used every lesson because everything uses the same rule. That's the message to get to them - that you’re not teaching four new things. It's all the same rules. They just move slightly differently. So they see the same models and they can see where the cyclic reactions close. That's very hard to demonstrate in two dimensions. The bigger models are much better as well.
Try and get across the bigger picture - everything you're going to do is going to be a model. Nothing is going to be right. Nothing is going to be wrong. Nothing is going to be exactly the way it is. Everything is a series of models.
Keep going back to applications in the real world. How is it that geckos can crawl up a wall, and sit on the ceiling without falling off? How is it they’re able to stay there with gluey legs or something? How do they maximise the attractions between the molecules in their feet and the molecules in the ceiling? Show applications that are powerful, and hopefully interesting, of the ideas that are important.
The nature of the students is that there are some that are interested in this topic in its own right. But many of them want to end up doing organic chemistry and pharmacology, or medicine of some sort. This is a theory which is too much physics for some of them, so you’ve always got to relate it back to their own interests.
