[yezhanquan]

1) There's even karaoke which allows you to be a seiyu, so I think it's pretty hot.

2) I think they do exist, just in lesser numbers than what anime may lead you to believe.

3) I think the length depends on the school. And yes, they do have bloomers.

4) According to Wiki, you're right.

5) I'm not sure. Most probably girls, I think.

6) Some do. Many do not.

7) Black Day is mostly observed in S. Korea.

8) I think they do. And no, you won't laugh if you get clobbered. They can be ruthless if they need to.

9 & 10) Yes and yes.
9) I think you can only sleep at the sick bay if you're really ill.
10) School bullying is serious business in Japan.

12) I think this applies to the older generation. I'm sure the younger ones won't mind you calling them by their first name.