When Mr. Bitters appears with money at the near end of the episode, if you can closely watch the TV on which the Suds-O commercial aired before Mr. Bitters appears, you can see there are no hands holding the box of Suds-O, and that Mrs. Knight can be seen in the background breaking the fight of Katie and Elliott up.
At the School of Rocque, the boys tend to switch seats throughout their time at the school.
When Mrs. Knight is about to home school Katie, she says "Let's start with history", then grabs the book on top of the book that says "U.S. History" and looks through it as if it were the history book.