My elementary school was 8:00 to 3:00, and my junior high was 8:30 to 4:00. High school was 8:15 to 3:15. There, usually teachers would get there between 7:00 and 7:30, and would stay until 4:00 or 4:30.
If the question is if a teacher's salary is proportional to the impact they have on society, then I would have to say no. That being said, I think that if teachers made as much as, say, doctors or lawyers, it would completely undermine the schooling system. Too many would simply join the profession for the material benefits. Some would even make their courses easier only so that their students would get better grades(and thus enabling them to keep their jobs). The focus would inevitably shift from helping others to helping oneself.
