I spent part of my workday looking at this. Out of the first 13 or so I found 2 true school shootings and a third I wouldn't argue either way. That is more than 75% of what I looked into were Like it said off campus college student, one that read like the cops shot a student when they missed a subject and 2 or 3 that were deaths at night or on the weekend. Gang fights the one girl who brought a .380 and shot herself in the leg was "a good girl" on the track team (tank tracks maybe).
The numbers they give are so messed up. I gave up keeping info after a while.
Added: Oh and I forget which school (college) it was but they forgot to report when a cop had a negligent discharge and the bullet went through 2 classrooms. So that school should have had 2 not just one.