Esteemsters - S1-E1
Continuity mistake: When Mr. O'Neill is talking to Daria and Jane, the board behind him has a bunch of arrows in a circle with a different word written next to each arrow. When the camera changes to a further angle with all three characters in the frame, the arrows remain on the board but all the words are completely gone - then appear again once the camera is close up to the board again.
Continuity mistake: In this episode, during the party, we see Tiffani (from the fashion club) for the first time, and when she speaks (just once in the episode), her voice is extremely different than the low monotone voice she has in later episodes. Here she sounds more Americanized and has a higher-sounding voice (similar to Stacy's).
Continuity mistake: In the Season 1 episode "Too Cute," Quinn mentions to Sandy that Sandy picked out Quinn's outfit that she's wearing. This could not be possible as Quinn had that outfit (the same one she always wears in every episode) since BEFORE they moved to their current town and before the girls met anyone in their school they first went to in the first episode.
