Ghostly graduate

Here's a link to a video report showing what is supposed to be a ghost. The report is a little flaky, but the video is interesting. They think it’s the ghost of a former high school student who has come back to haunt a teacher. That, or it's the shadow of the bat. I don’t think it’s actually a ghost or a bat. I think it’s a shadow person from a different dimension who’s just messing around.