Avatar: The Last Airbender Season 3 Episode 7 : The Runaway
Katara expresses her disapproval when Toph begins scamming Fire Nation civilians for quick cash. Toph thinks Katara is acting too motherly, and a rift forms within the group. To patch things up, Katara decides to pull a scam with Toph, but they are caught by Combustion Man. He uses them as bait in an attempt to kill Aang, but Katara's quick thinking saves the day.