Hello...
  I just noticed something that alot of fanfic writers usually end up doing.
It's a common mistake, and not really that important, in ways of story plots,
but it is a culture mistake. 
  Ever wondered why when Japanese high school students have a day off, it's
almost always sunday? Well, that's because japanese school kids go to school
6 days a week, unlike American students. Not only this, but with the class
room procedure, the teachers are the one that changes from class to class,
not students. Ah well, just trying to be helpful. ta ta... 
                Thank you for your time, Panther Wong...