I went to Catholic School and occasionally swam at a Catholic (Knights of Columbus) pool. Most of the other kids on my block went to public school and swam at a public pool.
Naturally, I thought there were two types of people in the world: Catholics, and "Publics".
It wasn't until an exotic (Jewish) family moved into the neighborhood that I was forced to re-examine my views on comparative religions.
A childhood belief about swimming pools

others believed things like this
- I grew up Jewish. Until I was about 10, I believed that everyone who wasn't Jewish was Catholic.— Philm35
- When a "mean girl" in early grade school asked me if I was a virgin I answered "no I am catholic."— Hilary
- I believed that the Kreepy Crawlie used to clean our pool, would follow me around the pool and eat me. — Mother-of-2
- I thought ducks couldn't fly - thats why they swam.— G
- I used to believe that i swam more than 2 hours I would become a mermaid.— M11cazares
- I used to think that a "pool shark" was an actual shark that lived in a swimming poolAnon