Hey, teachers, both ESL and good old fashioned first language educators: do kids annoy the shit out of you sometimes? Oh, absolutely! Children are unpredictable as hell. One day, the little angel can turn into a little asshole. Heck, they can do that in the span of one class. Then there are the ones who are never nice, the little sociopaths seem to want to stop at nothing to turn your psyche into a puddle of sad goo, waiting to be dumped into the nearest drain, flushed away with your self-esteem, hopes and dreams.
But not all experiences are like the bleak picture described above. If they were, I am not sure anyone would have the fortitude to withstand a day in a classroom, let alone a year. For those that could, you get my eternal gratitude, and any drugs I could find for you.
Even the assholes usually have a reason why they are assholes. And, like their swing toward terror from angel, terrors do occasionally swing back to angel, often unexpectedly.