Oh How We Met the Night That We Danced - S1-E5
Other mistake: When Rob is dancing with Laura and is supposed to step on her foot, his foot lands so far away from hers, it doesn't even appear that he stepped on it.

Starring: Dick Van Dyke, Mary Tyler Moore, Morey Amsterdam, Larry Mathews, Rose Marie
Oh How We Met the Night That We Danced - S1-E5
Other mistake: When Rob is dancing with Laura and is supposed to step on her foot, his foot lands so far away from hers, it doesn't even appear that he stepped on it.
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.