Couple of years ago, a friend of mine lent me his DVD when I told him I was yet to be acquainted with Onizuka. He could not believe it and literally forced me to watched it right away. Putting aside my studies (Yeah, I was in college back then), I dedicated my next couple of days to finish the anime.
It was time well spent.
After watching the first episode, I was totally enamoured by Onizuka Eikichi and his ridiculous crazy ways of handling matters in life. Here he was, an ex-biker gang leader, an emotionally fragile loser with no life, less social skills and a good heart whose aspiration is to be a great teacher. Mixed that all up and you get one character that fucked up a lot and get carried away from time to time with violence yet can't help being a good guy.
Onizuka was thrown into a class where the students have to deal with their own set of problems (a sad accurate reflection of modern Japan youth). Between skirt chasings and torturing the student, he managed to help them solved those problems, using his unconventional (read: retarded) methods which provide plenty of comedy and humorous situations. Onizuka was in the heart of it all. He, more than anything, what makes GTO as much fun as it is.
He is a one man hero.
The story is somewhat cliche and is considered episodic where several different story settings take place. However they are some very clever surprises and plot devices to keep the viewer poised for more.
The art and animation was adequate for its time but comes across as kinda outdated in this modern days. Nonetheless it fits right in with the mood the show aims to give you.
The voice acting from everybody fits well too with the characters (i'm not talking about the dubbed version). The variety amusing mood-enhancing tunes for background music will perk you up. As for the OP and ED songs, they were decent selections.
While there is a certain moral message to the anime, watch it for the sheer fun value. It will make you laugh, that's for certain, or perhaps it might even make you cry.