He shot a few more people than just his mother. He could have done that at home. All of these shooters have chosen a target they had some relation to, either they went to the school or they had some other prior history with it.
Still, the decision to attack the school, it's students and not simply one individual is why we are hearing about these.
Still, the decision to attack the school, it's students and not simply one individual is why we are hearing about these.