It all sounds a bit suspiciously like fancy dress. I was just round at a friend's house sorting out her printer, and she kept offering to lend me bat ears and witches hats and capes and stuff. I'll just state for the record that I Don't Do fancy dress - the school silly dressy-up days (Comic Relief, World Book Day, random theme days) is one of the things I am incredibly glad that I have escaped by not being a teacher any more. Although I'll absolutely defend your right to do fancy dress, if that's what you choose, of course.
She's now trying to persuade me to at least borrow some themed earrings.