Stupidity: Aunt Bee learns that a New York writer and his wife have moved to Mayberry and she invites him to speak at a Literary Club meeting which will be held at her home. By telephone, Aunt Bee gives directions to the writer's wife. She says, "We're a quarter mile outside of town" - but she neglects to say in which direction.
The Ghost that Sacked The Quaterback - S1-E15
Stupidity: It's hard to believe that prior to building a new stadium the owner wouldn't remove all the trophies and memorabilia from the old stadium's sports hall.
A Bad Reflection on You - S1-E38
Stupidity: The decision to risk revealing their identities to Bulk and Skull is one that the Rangers could have easily avoided. Since they tell the bullies to cover their eyes and ears, under the false pretense of a magic trick, they could have simply teleported to the Command Center, or any other secure location, and then morphed, well away from prying eyes.
The Tale of the Dream Girl - S3-E10
Stupidity: A boy walking through the bowling alley stops and lets Johnny pass, even though Johnny is supposed to be a ghost no one can see.
First Kiss - S1-E2
Stupidity: When Jeff Malone leaves the sandwich shop, he leaves the sandwich on the table. It would have been very easy for them to tell what was on the sandwich without needing to wait for Max to get home to recreate it. (00:02:41)