Here in America is to difference the private schools from the public...
But what is the reason in Japan for the divided idea of what kids should be wearing?
I know the question sounds stupid but is just plain simple curiosity...sorry

From C-Ray: Most schools in Japan need to wear a uniform and the main ...
Most schools in Japan need to wear a uniform and the main reason that I saw is to keep the social classes the same. Most schools here are based upon your intelligence and not how much money you are paying for school.

From sellatieeat: Most kids who go to school in japan wear uniforms. The ...
Most kids who go to school in japan wear uniforms. The uniforms identifies which school the child goes to. So if they do any bad stuff out in public, a witness can instantly identify the student and where the school the kid is from...

From Looking for the truth...: One answer talk about being able to identify students ...
One answer talk about being able to identify students through their uniform if they did something bad, but actually that is only a part of it. The uniform is the source of pride for the schools. School administrators want their students to be proud to wear the school uniforms and be associated with the school. They also want their students to have a sense of belonging, and inclusion. It sort of works for the high level schools, but it works in reverse for students of the lower end schools. You are right. Japan has become divided as to whether or not to keep uniforms or allow students to wear their own clothes. So many issues surround that idea it is not even funny. Money, identity, bullying, self-expression, Independence, to name just a few. But for now, uniforms are old school and people with the old school up bringing are in power. So nothing will change for some time. So, to answer your question directly. It all depends on who is running the school. If the board of trustees is progressive, they will not require uniforms. If they are old school, which most of them are, they will require uniforms. It seems very hit and miss, but the government doesn't want to get into the issue of legislating fashion. That would just open a whole other can of worms. Here is a clip from Wikipedia about school uniforms: Japan introduced Western-style school uniforms in the late 19th century as a part of its modernization program. Today, school uniforms are almost universal in the public and private school systems. They are also used in some women's colleges. http://en.wikipedia.org/wiki/Japanese_school_uniforms