When: Between (and partially in) the Boiling Rock Pt. 2 and The Southern Raiders
Where: Azula's (now stolen) Airship, The Western Air Temple
Summary:
Sokka and Zuko were talking, and Zuko learns Katara and Aang are NOT a couple (yet...). This would just be really goofy... Zuko going around saying, "They're NOT!" Like a crazy person.... he goes up to Aang and Katara and goes, "You're NOT!" and everyone (excluding Sokka) is wondering what the HECK Zuko is talking about!
So yeah... this is the first one to come to mind... more VERY soon!