How Come No One Knows About This?

http://en.wikipedia.org/wiki/Bath_School_disaster is the one I'm shocked is never talked about or taught in history classes to the best of my knowledge. Not to diminish Columbine or any of the modern attacks, but every time there's been one or a discussion of school attacks, no one seems to have ever heard of Bath. As far as I know it's the highest death toll for a school attack ever in the US.