For me as well, in the last years of Gymnasium they didn't control homework or even attendance much. I missed many classes in the last 2-3 years, because I preferred to stay at home and get some sleep or whatever. Or maybe it is more that I missed most classes by sleeping in class. Memories are hazy at this point. Which could be one reason that I've started to have these dreams where I notice I didn't attend this particular class all year and it's too late.