First, I for one,
highly doubt some school district or high school will have or has a
lunch lady or janitor that, at a moment's notice will snap into action like Steven Segal in
Under Siege or
Hong Kong Phooey.
Carrying a firearm &
learning proper tactics/skill training takes a long time & costs $$$.
Hiring properly trained security officers or guards is smart but they aren't cheap. If you want to cut corners(which many public school districts want) then the QC will nose-dive.
Hire off duty cops or patrol deputies? Sure.
In my metro area, the PD rate(hourly) for off-duty details is $43.00(min). The sworn deputies in the large county sheriff's office get $37.00(min).
In 2013, a parent offered to
pay the school for one deputy's wages for the entire school year. That's only one deputy at one campus.
As noted, there are + steps & security plans schools or universities can take. A few systems or plans work better than others in my view.
The Israeli concepts
will not work in most US schools.
Violence & counter-terrorism is a way of life in that country. You can't really compare the Israeli format or culture to the US.