My favorite paper I ever wrote was a 10 page essay in high school on what high school football meant to me. I got a college scholarship for writing it. I ended up not saving any copies besides the one I gave to the people who judged it. I never saw it since the day I wrote it.
I've written a lot of other papers from high school, college, and grad school that are awesome...my second favorite being 'Why I dont think Canada exists'. But that football scholarship was my favorite. I forgot all about it.