Other mistake: Rob's watch is completely blank. No numbers, no hands or the knob to adjust time. His watch is fake. (It may be that way in all the episodes but this is the first time I noticed it so far).
The Dick Van Dyke Show (1961)
1 other mistake in Girls Will Be Boys
Starring: Dick Van Dyke, Mary Tyler Moore, Morey Amsterdam, Larry Mathews, Rose Marie
Sally and the Lab Technician - S1-E3
Continuity mistake: When Jamie Farr the "Snappy Service" guy comes in and gives everyone their coffee Buddy throws a straw into the straw cup, but it falls down on the floor then vanishes, never to be seen again.
Laura Petrie: You wanna end up another Dwight Heatherton, go ahead.
Rob Petrie: Who's that?
Laura Petrie: Dwight Heatheron happens to be an excellent writer who is unknown because he gets no publicity.
Rob Petrie: Then how do you know him?
Laura Petrie: Oh Rob, he's famous.
Harrison B. Harding of Camp Crowder, Mo. - S1-E6
Trivia: Rob tells the police over the phone "Get a prowl car to 148 Bonny Medow Road." 148 was also Dick Van Dyke's weight during the TV series.