[rizu]

I did a six month exchange when I was 16. My American high school was sponsored by the university that had an exchange program with my sister city, so they carried the exchange programs down into the high school level. My school sent two students to Japan and the school in Japan sent two students to my high school. The experience will depend a lot on your host family, IMO. I was fortunate enough to get a host family that encouraged making friends and doing extra-curricular activities, and during my summer vacation they took me to a couple different cities.

HOWEVER the other student from my American school got stuck with a host family that was super strict, wouldn't let him go to hang out with his friends after dark, and if he broke any rules the mom called up our teacher and told on him. He ended up breaking the rules to have fun anyway, BUT he almost got sent home three months in.

School in and of itself, we attended a public school, were placed in a normal classroom, and went to most of the normal classes except two. During those times we were taught Japanese history in English, and then had a Japanese language lesson. All in all, it was pretty much a full immersion.

The companies such as Rotary and such I know have some pretty strict rules so if you don't mind following them, then go for it. If you want to be able to do your own thing and just have to follow basic school rules, then try to find a city exchange I guess. But if you have family there maybe work something out with your grandparents and try to make an agreement with a school in their city.