This is the sequel to the manga GTO (Great Teacher Onizuka). This takes place directly after the Teshigawara arc.
WARNING: MASSIVE GTO SPOILERS
Spoiler (mouse over to view)
After guiding the infamous Tokyo Kissho Academy through a crash-course of his unique brand of life-lessons, a battered and bruised Eikichi Onizuka takes a well-deserved trip to his hometown of sorts, a typically quiet surfers paradise called Shonan. Unfortunately, with child neglect and abuse becoming a global phenomenon the self-proclaimed GTO (Great Teacher Onizuka) quickly finds himself back in the saddle for what he hopes is a painless two-week long field trip with some teens in need. And while Onizuka's curriculum may not rely on the reading, writing and arithmetic that is common in most classrooms, he has more than a few good lessons in personal development, fisticuffs and fun to teach a new generation of trouble teens.