you kiddin'?! no one changes his haircut exept for in book 3 where the whole gang including katara changed their haircut. besides,katara acted badly with zuko because she was sad the fire nation took her mother. i am a zuko fan like you but i don't think katara is actully "mean"
+Kolin327: Yeah, he accidentally burned Toph. It was in the very last episode. (I think). When Toph that she could trust Zuko to teach Aang firebending, she thought she should talk to him. So she went to his tent, and when Zuko heard some noises, he used his firebending without checking who it was and burned Toph. Toph crawled all the way home! :( Then when Toph explained to everyone what happened, Katara was mad.
When Zuko asked if he could teach Aang but Katara started yelling at him and then he burned Toph! He didn't mean to! Come to think of it, Katara is kind of annoying...she has the same hairstyle EVERY SINGLE TIME, SHE YELLS AT ZUKO, And she sometimes just annoys me at some points... Sorry people! Katara fans, don't hate me, it's just my opinion.