Groups in Japanese schools!!

There are not so much groups in Japan than in America.
I went to a private girls school for 6 years (junior high & high school). My school was strict in rules! Like skirts should be no shorter than 5 cm above your knee, tie your hair up if it touchs your shoulder with hairband(black or navy), etc.....We dressed the same, had the same bags, so the groups weren't made by our appearances. Still, there were groups. For example, the noisy ones and the silent ones.

Last week, my group was really discussing about coolness. I really want to hear the voice form Colorado students, what kind of people is cool to them.
By the way, in our group we discussed by picking up a drama. You can see the opening from
http://jp.youtube.com/watch?v=VPSDGXFB4xs
The boys thought the first guy that apears is cool, but the girls thought the second guy wearing a white suit is cool.
What do you think?