I have watched this, because I can be considered a fan of EunJi and this looked like it would offer light hearted comedic relief. I guess the show did not disappoint too much in that regard. The acting ensemble was truly outstanding, some of Korea's best actors appear in this drama & their performances were up to standard. EunJi plays the exact same character as in R97, I don't mind typecasting in this case, since the show was built around this specific persona. The OST is okay, although it's not memorable at all.
I liked the main couple, their slow, but steady development in this genre is perfectly fine. I wouldn't say that they've had off the charts chemistry though. I hate triangles in general, but here it was bad in the sense that it served no purpose, generated no meaningful tension, felt like a writing quota type thing, you know how there is always a gay guy in american sitcoms as of late.
There are some obvious problems with how the characters & how character development are portrayed in this drama. It's always annoying, when a show isn't preproduced & the writers make major changes midway, because of feedback, or because there is outside pressure from sponsors. The way how they changed SooAh's character, or almost everyone's character in the White Tigers group mid way makes no sense whatsoever. I was applauding SooBin's performance in this "villainous bitch" role, but unfortunately she went from a villain to a troubled girl with a sad background & from that to a kind angel in the finale, this made very little sense to me, It could not have been any more unrealistic.
South Korean society has some rules & behaviors that are really backward and I dislike it, when these things surface in dramas. In SassyGG the primary obstacle for the main couple comes from the impending marriage of their parents. "Oh no, what will I do, if you become my dongsaeng" Other dramas have exhausted this trope to death too.. Not cool!

Now the main reason why this drama is bad is because the story is just terrible. It's normal for romcoms to have meaningless underlying storylines, or that the story is not in focus, but there is gotta be a limit right? I'm perfectly fine with the school slice of life genre, but the things that happen at this school are just plain bad writing, perhaps it's not as bad as in the recently aired drama "My Strange Hero", but it suffers from many similar problems, namely outlandish teachers, kids breaking under the pressure doing outlandish things, ajumma armies demanding justice and my favourite: kids fighting the school's corrupt leadership/principal. Abusive parents doing abusive things cannot even count as abnormal in this drama...

I do not regret watching this, EunJi kept me entertained all the way to the end, but I will not watch this again for certain.