These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Great Teacher Onizuka
Cargo Ship: At times the only thing that seems to prevent Uchiyamada from marrying his Cresta is the unfortunate fact that it's kinda sorta... unconventional.
If violence doesn't do the trick, more violence will. It's perfectly okay to put your colleagues' and students' life in danger when you're a teacher if there is a moral lesson behind the action. Also, some examples of Onizuka "resolving" problems of his students fall into this.
Be Yourself, Tokiwa. When you've been gang-raped, lost your trust in the men and humanity as a whole, when you feel insecure and seen mainly as a sexual object by the opposite sex... remember that you're a girl. You can always cry. Admittedly, when put in context his suggestion is actually better than her solution. Baiting guys and beating them up. It nearly got her gang-raped a second time.
Fan-Preferred Couple: Onizuka and Urumi, at least as far as the majority of the western fanbase first introduced to the series through GTO is concerned. The pairing tends to get more support due to the opinion that Urumi has more of a developed personality, while Fuyutsuki too obviously fills in the role of obligatory love interest.
Think about the last middle schooler you saw. Now picture them pregnant, living alone, and holding a job. How exactly would a disowned 13 year old rent an apartment without a credit history, raise a child by herself, and in the most expensive city in the world, all with no outside help or child services intervention? Either Japan has the world's greatest and most beneficial welfare system, she had the world's nicest landlord, or the writers are greatly exaggerating for dramatic purposes.
Why didn't the school just let Urumi skip a few grades? They knew she was a prodigy. It's not like the Japanese school system doesn't allow that, as they did it in Azumanga Daioh. Or send her on a foreign exchange program to give her a challenge of learning in a different country, like they usually do with advanced students? But then we wouldn't have a plot, now would we?
Actually, the Japanese school system doesn't let students skip years. Chiyo being allowed to skip those years she skipped is full-on Rule of Funny.
Kikuchi has his moments, being one of the geniuses of Class 3-4.
He pales in comparison to Urumi though. Selling the virginity of the girls who tried to frame 'her' Onizuka to a bunch of perverts scores fairly high on the Bastardry scale.
Marty Stu / God-Mode Sue / Anti-Sue: Onizuka, big time. Superhuman strenght and endurance? Check. Never lose a fight or an argument? Check. Able to seduce countless girls despite his disgusting habits and hobbies? Check. Is so cool a class normally full of hate for teachers start to love him in several weeks? Check. Every person who dislike him or go against him is humiliated repeatedly? Check. Can humiliate them and get away with it? Check. Do they all admit he was right in the end? Check. Succeed in exams despite being depicted as an idiot? Check. Center of attention at any time? Check. People starting to imitate his way of living? Check. Survive 4 bullets in the guts before unleashing a Humiliation Conga against the shooter? Check!
On the test, it is outright stated that Sakurai fixed it so that he would get top score (though we never get to see Kikuchi's calculation of his real score). On getting away with things, it's also implied that Sakurai is covering him (and it is shown that her connections allowed arson and attempted murder to be swept under the rug). Beyond that, Refuge in Audacity and Rule of Cool are attempted to cover up his rather advanced abilities to tie up the plot.
Nightmare Fuel: Onizuka is mistakenly forced into a marriage with a Kuchisake-Onna; her family share the same trait of a Stepford Smiler with saw teeth. Onizuka also encounters one in Okinawa, though it was a young girl and actually quite nice.
Many people may not realize that GTO was an almost direct sequel to a lesser-known manga series, Shonan Junai Gumi. They most likely assumed that GTO started in media res, though it could just be the fault of TokyoPop for Americans.
Shonan Junai Gumi was marketed as GTO: The Early Years in North America and UK, but it was marketed as Young GTO in France.
Tear Jerker: While Onizuka is dying of his Game-Breaking Injury, his old Nakama Ryuji refuses to believe that Onizuka could be hurt in any way and says that he can not die. When Onizuka's heart stops beating, he punches him in the chest hoping to wake him up, crying.
In the live-action drama episode 11, Onizuka was being forced apart from his students. As he was being dragged away, he tells each of his students something relating to their interests (showing just how well he got to know them) or a final piece of advice.