The Southern Air Temple - S1-E3
Other mistake: When the gang is in the Hall of Statues of Past Avatars, Katara points out the avatar cycle pattern of statues and Aang zeroes in on Roku's statue. The earthbender avatar statue next to Roku is of an unknown man with a sword, not Kiyoshi. (00:12:50 - 00:13:35)
Other mistake: It appears as if Steve is holding 3 $20 bills when he supposedly received $50.
Other mistake: In the voice cast list, the Groom's Father appears twice - with two different voice actors - and the Groom's Mother is not even listed.
Other mistake: In the sequence with Love Delux destroying the hotdog stand, notice that the sign is crudely drawn and does not resemble the look of the stand. It even says "Hot DOC" (00:06:30)
Gopherville - S1-E1
Other mistake: In "Sock Safari", when Toopy finds a red thread, his left hand with his glove disappears instantly.