We learn that the Fire Nation took over Omashu at the last few seconds of Season 2 Episode 2 "The Cave of Two Lovers." But the kids actually go into Omashu in the next episode
Katara gets burned in the episode "The Deserter" Aang is trying to learn firebending and accidently burns her, but after that she learns that she has healing abilities by dipping her burned hands into water.
The episode is from Book 3 (Fire), Episode 42, and it is called "The Headband."
The episode where Aang attends a Fire Nation school is "The Headband" from Book 3: Fire. It is Episode 42.
Sozin's comet:Avatar Aang (part 4)
yes they were on the last episode
Towards the end she starts to like aang (watch last episode)
the episode was called "the fire bending masters"
Season 2 Episode 20
yes in the last episode of avatar the last airbender aang and katara kiss
I think because he is in the fire nation's clothes.
it is on episode 10 of book 3..
The Last episode was Avatar Aang which was part 4 of Sozin's Comet