I’ve been thinking that for someone who didn’t choose the teaching career for himself (and quite honestly, I think he actually hated teaching), Severus appears to put quite a bit of effort into some parts of what constitutes teaching. (And I don’t mean the way in which he treats his students here. I think that we all agree that even if some of his behaviour wasn’t so unusual to see in schools in 1990s’, they’re widely considered unacceptable these days. Sadly, it doesn’t mean such situation don’t happen any more.) But back to the main point.
‘The ingredients and method –’ Snape flicked his wand ‘– are on the blackboard –’ (they appeared there) ‘– you will find everything you need –’ he flicked his wand again ‘– in the store cupboard –’ (the door of the said cupboard sprang open) ‘– you have an hour and a half... start.’ (OotP, chapter 12)
Contrary to what some people want to believe or remember, save for that one DADA class in POA he didn’t use textbooks in his class at all. It is my personal opinion, with which not everyone must agree, that making students read a textbook and have all the classes done this way takes practically no effort from a teacher. You (general you) just assign the reading in the class and your job is done.
Severus, on the other hand, wrote his directions on the board and talked a lot, providing his students with useful bits of knowledge (even if they didn’t realise it at first). Remember from where Hermione got the Polyjuice Potion idea in CoS? ‘Snape mentioned it in class a few weeks ago –’ (CoS, chapter 9) It would also appear that some part of the instructions were either spoken or verbally stressed, too. [Didn’t you hear me say, quite clearly, that only one rat spleen was needed? Didn’t I state plainly that a dash of leech juice would suffice? (PoA, chapter 7)]
From that short fragment one more conclusion may be drawn. Severus took care of the ingredients in the cupboard. To know that students will find everything they need in the cupboard, he either have to supervise inspections of the stores or, which I find more likely, he did the inspections himself. Which is an additional taks we may add to the list of his tasks.
Another matter ties in some way in what was said above - his classes were on the subject. Potions were about potions, DADA was about DADA. Even his class about werewolves was on the subject. Both Hermione and Parvati mentioned that they weren’t to study werewolves yet. So, the subject of werewolves was in the syllabus, but somewhere later in the ter,.
I would also argue that his classes were useful. Even if he didn’t teach his students how to brew the Polyjuice Potion, he mentioned it, giving the students some idea that some people they will meet may not be who they seem to be. He taught them about the antidotes to most common poisons (mentioned in GoF). He taught non-verbal magic, which is a dead useful skill (happened in HBP). He also made them research ways of fighting with the Dementors (also HBP), not just one spell, which I suppose came from his knowledge of how difficult the spell was to learn and other circumstances that could affect the skills. (Which I think some people tend to forget, judging by Harry’s own success and that of DA members.) Even his lesson about werewolves may have come in handy when werewolves joined Voldemort’s forces.
Next matter - dealing with accidents. It would appear he was always prepared to deal with whatever could wrong in the class, either immediately sending kids to the hospital wings, like it happened with Neville in the first class [‘Take him up to the hospital wing,’ Snape spat at Seamus. (PS, chapter 8)] or dealing with it himself [‘Silence! SILENCE!’ Snape roared. ‘Anyone who has been splashed, come here for a Deflating Draught. (CoS, chapter 11)].
And not surprisingly he was not forgiving about the real harm made in his class, caused by something he could consider an ill-advised joke. [When I find out who did this... ‘If I ever find out who threw this,’ Snape whispered, ‘I shall make sure that person is expelled.’ (CoS, chapter 11, after finding out a firework in the cauldron)]
Mind it, these things don’t make him the perfect teacher™. If anything it adds to the duality of his character. I think we can all agree that this man is a walking contradiction. We all can agree he had little to no patience and way too often his frustration got out of hand. However, it doesn’t mean that everything he did was wrong simply because he was Severus Snape. It all makes me think that he would force himself to do some things properly or in the matter he considered proper, even if he hated them greatly, and he did it because it was expected of him. That effort he put in some aspect of his job is almost surprising in a way, taking into consideration that teaching was well... more like a cover for his real role.
