Visible crew/equipment: When a few of the kids pass the note from Linda to Beaver he puts it in his pocket, then it cuts to the class bell ringing, and there are multiple chalk marks on the floor where Beaver and other kids stand. (00:03:00)
Leave It To Beaver (1957)
1 visible crew/equipment mistake in Party Invitation
Starring: Barbara Billingsley, Hugh Beaumont, Jerry Mathers, Tony Dow
Visible crew/equipment: The shadow of the boom mike is visible in the background when Wally is saying that June looks "ritzy". (00:14:45)
Eddie Haskell: Look Sam, if you can make the other guy feel like a goon first, then you don't feel like so much of a goon.
Wally Cleaver: I don't get that.
Eddie Haskell: Of course you don't. That's because you never went to kindergarten with a home permanent.
Captain Jack - S1-E3
Trivia: The episode "Captain Jack" was the first time a toilet was shown on TV; the boys buy a baby alligator and Wally is shown putting it in the toilet tank. The network censors were so spooked by the thought of showing a toilet on television that they delayed the episode. And when the censors finally relented, the compromise allowed only the toilet tank to be shown, not the bowl.