sndmn11
"DADDY"
And they may be the first, only, and/or "hopefully" the final defense after said suspect enters the school. Pretty much like any and every other situation out in society outside of school.
Normal every day citizens are the ones that are first on the scene of most every crime.
Bingo! Right place right time, leaves the everyday citizen exponentially more capable than the best trained shooter. 99.9% of the time and work in an active shooter situation is working to and identifying the suspect. If those on site are allowed the ability to defend, then the time penalty does not exist due to the imminent opportunity to defend.