Character mistake: When Missy is at her audition, Courtney and Whitney get annoyed and tell her to do a sequence, (front handspring stepout, roundoff back handspring stepout, roundoff back handspring, full twisting layout). However, when Missy starts the sequence, she starts with a cartwheel instead of a front handspring.
Character mistake: When Boris and Natasha (Jason Alexander and Renee Russo) are at the airport (just missing Rocky, Bullwinkle and the FBI agent) Natasha says something about "Moose and Squirrel don't even know our names", yet earlier in the courthouse scene, Bullwinkle says something about Boris and Natasha being real people and Rocky and Bullwinkle still being cartoons.
Character mistake: After Charlie and Irene leave the Rhode Island station for New York, the female officer refers to her boss as Captain, when he is a Colonel.
Character mistake: When Bob Balaban is talking about how his ancestor founded the Mayflower Dog Show in 1875, he points to a painting which is meant to depict that time. However, the clothing in that painting is demonstrably from the 1860s - styles had changed radically by the 1870s.
Character mistake: When Barry and Rob are in the record store discussing Evil Dead 2, Barry makes a comment about someone offscreen making shotgun ammo in the 14th century. That plot point refers to "Army of Darkness" (the third installment the Evil Dead series), rather than Evil Dead 2.
Character mistake: James Lear is described as a Sophomore Lit major in the first scene, and at the end of the movie at Word Fest as a Junior.
Character mistake: Sam and Maurey were watching TV news coverage of Kennedy's assassination (11/22/63). When Petey got home (around 12:05 PM MST), he tried to change the channel, then said, "Mom, Maurey won't let me watch 'Rocky'." Laurabel/Mom said, "You know he watches 'Rocky' every afternoon." But school was let out early due to the assassination, so Petey would normally be in school at noon and therefore not be able to watch "Rocky" at that time in the afternoon. (00:21:30 - 00:23:17)