Class Scheulues

[psion_x]

No: HPFGUIDX 35126

After reading Goblet of Fire I noticed that when the Beauxbatons and 
Drumstrang students arrive at Hogwarts on October 30th at 6 p.m 
classes end a half hour early. 
So this means the last class of the day finishes at 6.00 p.m but 
classes start in the morning at 9.am, which means the students have a 
nine hour long day. 
Although there are breaks between classes these seem at the most ten 
minutes, so how does it add up to nine hours? As far as I can figure 
out in Harry's Fourth year he has three/four classes a day.So in 
order to add up to nine hours each class would have to be two hours 
long, a double lesson (which I take to mean as two lessons back to 
back) FOUR hours long and lunch THREE hours long!
Does anyone else have theory's on how this could work?

Anonymoose :O)
I'm writing a fic and I'm having trouble figuring out when everyone 
has free time, which is why I'm interested in the lesson scheulue.