I used to believe the word seal had two different spellings. If you mean the animal, you'd spell it "seal" and if you mean the rubber band thing used to close lids, you spell it "seel".
A childhood belief about speaking

others believed things like this
- I used to think the Back Street Boys were black. I also thought Seal was a boy band. — Tufty
- I used to think that an imbecile was some type of seal, before knowing that it meant someone stupid.Anon
- I used to think that a sea lion was a hybrid of a seal and a lion.Anon
- i used to spell eight "ate" cuz of the stuped: why was six afraid of seven, cuz seven ate(8) ten joke...— 8
- When I was, like, three, i thought my cat was an evil sorcerer and would cast a spell on me. XD— Bobbet
- When my sister told one of my brothers her e-mail address, he thought to spell out “at” instead of typing “@”.— EJ - no longer computer illiterate!