Of course you can run the numbers and realize this plainly falls way below the level at which anyone should be using that use-case as a justification for anything.
(nb. the vast majority of school shootings you'll see in the statistics aren't the sort where kids having phones matters, they're e.g. targeted attacks on a single person, gang- or otherwise crime-related targeted attacks, violence that just by happenstance takes place on school grounds outside and perhaps not even involving any students or staff; all of which tend to be over almost as fast as they start and aren't an ongoing threat to bystanders once they're over, and even those aren't terribly likely to be something a kid is present for during their school career, on average)
... to be more clear, if you run the numbers, they're still kinda not. Our reaction(s) to them aren't rational (though, one can understand why)
I am somewhat sympathetic to arguments that lots of things we took for granted growing up really are not especially acceptable today but there are limits.
I'm not sure smartphones have improved on this? If a kid gets a call in class the teacher's almost immediate reaction is annoyance, because there was no chain of authority that led to that distracting element. Now the kid's on the defensive and has to explain that it's their parent, and the whole class gets to wait while the kid awkwardly has this conversation while simultaneously communicating with the teacher that it's a legitimate request, etc. And that's for legitimate emergencies, to say nothing of the troublemakers that will intentionally coordinate fake calls to get out of class and hang out with their friends.
Allowing smartphones for everyone is an unbelievable distraction.
ADHD tangent aside my point is: I can see the need these days, however I like the idea of a dumb phone that just has the basics. Definitely no tiktok, facebook, etc.
But let's assume a rare mass shooting actually happens (I forbid this thought)...will there be any point calling your kids? A phone will be more of a liability than an asset at that point..
That we have so many school shootings is shameful.
That we've decided a good reaction to them is to traumatize huge numbers of students (and staff! My former-teacher wife has stories...) over something that's, as shameful as the cases of it are, in fact extremely unlikely (specifically, an indiscriminate mass shooting at a primary or secondary school) is also shameful.
During active shooter situations, the school isn't going to call the parents of the students. They have other things to worry about. The kids are calling their parents directly.
To do what? Come save them Delta Force style?
If such an unfortunate thing happens, the kids are dependent on law enforcement, not parents, for safety.
That would probably be the primary thing I'd imagine the parent is worried about. If you have a kid in a school with feckless police that stand outside while kids are getting shot at, then yeah, some parents probably are a better rescue option.
Schools have communication plans for exactly this situation.
If you have a kid in school, you will be aware that schools have no qualms about communicating directly with parents via automated texts, emails, and phone calls, constantly, about nonemergencies. The volume of communication from schools is overwhelming. Putting out a notification about an active shooter incident would be easy. The trick would be getting the school admins to just send it out as a simple message, and not as a link to a Google doc containing a scan of a printout of the notification.
the parent wants to know if their special snowflake(s) is okay. these automated systems are absolutely not going to tell them that, and aside from that information, anything else is just seen as the school trying to placate people.