My secondary school class teacher, Mr Yam, is a very good teacher.
He always tells us "frustration is the mother of success". He is a authority in school because of his 30 years teaching experience. He always use his wooden ruler to hit lazy students but he never fear of any complaints. I remember that when I was study in From 5 and 6, 6 wooden rulers were broken by hitting our class. In Physics lesson, he told us the most effective learning method is doing the past paper.
By his theorem, he believe that if we repeat solving the exercise and checking the answer many many times, when we meet the question like we done before,we can write the answer automatically without any thinking process. With my experience, he is absolutely right.