Japan with 18-year-old boy
 

My son's dad is taking him to Japan for eight days as a high school graduation trip. They're planning six days in Tokyo and two in Kyoto. Is there any particular section (or list of things to do) of Tokyo that appeals to teenagers? Also, Jack has expressed an interest in "hot springs." I know there are lots on Hokkaido, but I have no idea how accessible that is from either Tokyo or Kyoto. Are there any spa/springs near either of those cities?
Thanks.

There are a lot of hot springs all over Japan not just in Hokkaido. This site will list them with an option to rent a ryokan or two.

http://japaneseguesthouses.com/index.htm

Lots to do for a teen in Japan. In Tokyo you might want to start here on a Sunday morning.

http://www.japan-guide.com/e/e3006.html

Aloha!