I thought the beatles' lyric "I'll give you everything I've got for a little peice of mind" was "I'll give you everything I've got for a little peice of pie." I always wondered why he wanted pie so much.
A childhood belief about misheard lyrics

others believed things like this
- When there was an advert for a "3 peice suite" i thought it was a shop selling 3 P Sweet's!!!— Kate Parker
- I thought Maria Carey's 1998 ballad was 'I'd give my arms' instead of 'I'd give my all'.— Briony Maggs
- I used to believe that the lyrics to Bon Jovi's "You Give Love a Bad Name" were "You give love a Band-Aid".Anon
- When I was a kid I heard that the Beatles did acid and I wondered if they melted from it.Anon
- I always wondered why shepherds washed their socks by night. (correct lyric: watched their flocks)— MaggieNJ
- When I was little I thought if you were sick the only way to get better was to give it to someone else.— Jen