Rochel Imeinu told Lavan that she could not get off her camel when he came looking for the terafim because she was pregnant. (not exactly, but I guess a small child would not understand the real explanation)
Mordechai was Esther’s uncle. (that one contradicts what is clearly written in the megila, “…bas avichayil dod mordechai” dod is referring to Avichayil, not mordechai). To be fair, I don’t remember a specific teacher actually saying this, but I remember it being “common knowledge”.