Better than Average Cory - S6-E5
Continuity mistake: When Rachel starts writing down that she is choking, she knocks a cup of water off the counter. After she spits out the hot dog she was choking on, the cup has reappeared on the counter. (00:06:38 - 00:07:00)
Better than Average Cory - S6-E5
Deliberate mistake: When Rachel is choking and writes down "I'm choking to death" on the paper on the counter so Jack will help her, you can see she is just scribbling the pen across the paper and not actually writing anything. (00:06:36)
Better than Average Cory - S6-E5
Character mistake: The placard next to Alexandra Nechita's painting "Peace Collector" erroneously calls the painting "Peace Collectors." Nechita herself appears in this episode, so it's odd that they got it wrong. (00:02:49)
Answer: Topanga's middle name is never specified. Considering her sister's name is Nebula Stop-the-war Lawrence, Topanga's is probably something equally unusual.