Motive.... uhhhhh, I'm not really sure there is a reasonable motive for shooting 7 year olds.
Some reports are saying the shooters mother was a teacher at the school and was killed at home. Seems to be a lot of conflicting reports, so who really knows. Even if that's true I have no idea how that ties into shooting small innocent children.
Unbelievable.
Of course there's not a reasonable motive. I just want to know why somebody would murder children. Why... That is the most asked question in times like this.