There should have been a resource officer on campus. If not that school district failed at protecting their students.
It's going to be an eye opening and sober AAR of this shooting.
There were two resource officers on campus during the Sandy Hooks shooting. Having a gun and a badge doesn't make you superman. What they need to to really promote the Texas law that allows teachers and staff to carry weapons after they have the special training. My district does this, and they have periodic drills to maintain their proficiency.