I think GTO is rather highly over rated. The drawing isn't that great and story gets somewhat repetitive with only different people at it.
GTO starts out as not all that entertaining. It doesn't make you laugh out loud - well I never bursted into laughter even once, there's no "awwww" moments of romance, there's really nothing great. But, it is extremely addictive. Once you start, it's really hard to stop. But, that's really the only good quality if you ask me. If you consider it a good quality anyways.
There are several scenes in GTO that seem like the author is trying to use his/her brain quite a bit with the so called smart kids or teachers. But they only get good grades and they honestly aren't that smart. I could come up with better solutions to problems than they do in 5 seconds. The so called prodigy kid doesn't show a single sign of comming up with a clever plan. I think the author somewhat lacks the ability to come up with some really great and makes you go "omg, i never thought of that!!" Rather, most end up as simply being lucky or there was someone else's back hand that happened to have helped him. The same pattern continues through several arcs of this manga. This was the reason for me to drop this manga after reading more than half.
On another side, I think this author had a really bad time with his/her teacher or something. There's so much anti-teacher bashing in this manga that it's almost sickening. And i'm not even a teacher!! Other than the "pretty teacher", "the nurse" and onidzuka, every other teacher is a bad guy with some serious mental issues.
The manga tries to show the so called biker's real life and some real life problems, but the entire manga is just.... really unrealistic. Some stuff in the manga certainly does exist in real life, but all concentrated on one place like that with high prestige school? Give me a break. I know i'm reading a fictional story that is made to be exciting, but so many of the plans and tricks that happen are rediculously unrealistic with extremely easy solution if you only have half a brain occur repeatedly. Honestly, I dislike manga where the main character is a complete moron. He can get tricked a million times and will fall for something almost identical to the last time. He absolutely has no ability to see who doesn't even like him when they are even screaming all the time about it.
Oh btw... this manga has the "enhance" feature in computers vs porn and any other so called mosaiced... It's about a great as some CSI:NY episode where someone goes "I'm going to make a GUI on VB to track the IP". WTF!!! Please don't make bs....
Yea... this manga... not that great.