I used to believe that all things that tasted minty (Gum, peppermints) worked just as well to clean your teeth as mouthwash did.
A childhood belief about chewing gum

others believed things like this
- I thought peppermints were made with peppers.— Lucy
- A friend on mine thought that smoking menthal cigarettes would make his breath minty fresh.Anon
- I used to think that the things you get in your teeth were called feelings.Anon
- I used to believe that eating burnt toast would make your teeth whiter and would brush your teeth for you.— Natasha
- I used to believe that if I didn't brush my teeth at night, ants would crawl into my mouth and eat my teeth.Anon
- Until I was about 8 I believed that your back teeth keep growing in until you have a full circle of teeth.Anon