Continuity mistake: When Billings offers Prof. Erskine Tate a nightcap, the confetti on his shoulder changes position and quantity in the close-up on Daniel Davis. (00:03:15)
Continuity mistake: When Professor Tate congratulates Eric Lane for the improved grades, the two have a playful banter, and Tate says he's "happy to be proven wrong." Christopher McDonald has to wipe off some streamers that got in his hair. In the next close-up, he still has streamers on his shoulder despite the fact he brushed them away entirely. A similar mistake happens later on when he is carrying the unconscious professor out of the room; streamers suddenly are all over him from one shot to the next. (00:02:40)
Answer: If it was ever found out that she was at Terry's house before he was killed, there's a possibility that a lot of people would have begun to suspect her of murdering Terry. By claiming that she wasn't, she was hoping that people wouldn't accuse her of the murder.