Physics
But I remember with what fidelity I attended my Physics tuition classes. Almost the whole of Psbb (my school) used to attend Mr.Sundaresan's classes. He was a great disciplinarian and punctuality was something he insisted more than studies. We were made to go back home in case we were late even by a minute. Completion of assignments on time and scoring above 65% in the class tests was mandatory. All of us used to dread his assignment discussion classes, where he would randomly ask people to give the answers to the given problems. If you hadn't solved the question, you had to submit the same problem done about 20 times.Another thing that I always admire about him is the way he remembers the name of each an every student who attended his class. (80 per batch and there were 2 batches per year)
More than the knowledge that he passed on, the passion for the subject that he imbibed in each one us was terrific. I used to loathe Physics until my 10th standard. But today I owe everything that I learnt in those 2 years to him. Be it, Punctuality, Moral Values, Principles and of course the love for the subject !