To adults who don't have sensitive ears cursing does not indicate crudeness OR ignorance actually. A well timed curse word can emphasise a point, make a joke complete etc. You seem to have a very narrow and silly view on what are essentially just words. You put the meaning to them, and I'd suggest that if you see cursing as ignorant then you're the ignorant one. They are words.
And do I curse in school papers? I don't know - you tell me. Let me ask you though, ever study a book IN SCHOOL with swear words or sexual references in? Yes. And you tend to study important or classic words. So unless you want to claim that classic authors are crude and ignorant you've kind of made yourself look silly.
Kthxbai.