Japanese high school groups

Let me introduce Japanese high school life, especially, I will focus on some groups of high school students. I have read a part of “Freaks, Geeks, and Cool Kids”. That book said that in American high school, there are many kinds of groups. Some people who don’t like school make a groups by themselves and the others who love cartoons make a group by themselves and their fashion are actually different from the others..etc...
I will tell you how was my high school was. My high school had some groups also, some people who likes studies accompanied with themselves but the groups doesn’t have their names just like American one, and the groups didn’t have conflict each other, I guess that students made their groups because they just feel comfortable to be with people who have same hobbies and similar interest. In Japan, we now studying American high school life, and this (writing about Japanese high school life and ask questions to you!!)is the homework, so please comment!! See you!!