My dad told me when I was about 7 or so that the sign indicating a median is ahead (looks like a shoe imprint with an arrow going around the right of it) meant that there were pedestrians trying to cross the street ahead, and you had to drive real fast to avoid them.
A childhood belief about road signs

others believed things like this
- when I saw a sign with a deer on it I always thought deer had to cross the street by it. like a cross walk— only me
- I used to believe that north was always straight ahead. I could never face south, but I knew it was behind me!— Bruces
- my mom believed when she was little that a street sign that said don't walk meant you better run.— Sara Mclen
- I used to believe a dead end sign meant there was a graveyard at the end of the street or zombies — Still Out There
- I thought that the "don't walk" sign at crosswalks meant to run across the street as quickly as possible!— richard
- Street signs with the upward pointing arrow was for airplanes. — Tammy