I found this video on the Courier Mail site this morning. The story is about teaching English in Japan to small children. I taught in China, and at high school and university, but it reminds me of the sort of classes that were conducted in the hagwans in South Korea.
The teacher talks about the long hours - 8 classes in a day, of perhaps 45 minutes. It wasn't clear. In China we worked around 16 hours a week in the class room, but each contract will be different. If one is employed in a the private language schools the hours are much longer.