I'm sure you can provide statistical confirmation of that statement depending on how you define guns, carry, and violent crime.
I could provide confirmation, sure. No need to resort to odd ways to define guns, carry, or violent crime, though. There would be little point, though, in this case.
Just as I call upon my knowledge of rural Pennsylvania during buck season to prove that everybody in town can be armed and there will be no crime, violent or otherwise.
Sure. The two statements aren't actually in conflict, though. Rather, when one selectively limits the field of play, like you just did right after trying to insinuate that I was doing that, it's not hard to come up with cases where a general trend is not as applicable.
When the only solution being offered to stop school shootings is to reduce the number of guns, it sounds like the whole problem is being blamed on the number of guns.
Given that that's not even close to the only solution being either suggested or pushed? Your premise is simply false and the arguments that you've been building on that premise can simply be dismissed out of hand.
When the solution being offered to stop school shootings is to ban a type of gun that already been banned
Previously. The assault rifle "ban" ended in 2004. Are you maybe talking about something else, though?
or ban a type of gun for which other guns can be substituted,
Would they be just as effective? I've heard noise about AR-15s and guns that have similar features that increase their potential to kill en masse dramatically over, say, hunting rifles, but none over, say, hunting rifles or things that can shoot projectiles, as you tried to reductio ad absurdum to earlier.
it still sounds like the whole problem is being blamed on the number of guns but that the people offering up the solution are stupid, uninformed, and/or have ulterior motives.
Given how wildly false your premise is, your complaint makes you sound like you are stupid, uninformed, and/or have ulterior motives.
When your rebuttal is "What you said is so stupid it's obvious you're wrong" means you don't have a rebuttal. Don't worry, there's alot of that around here.

No, given how stupid and/or uninformed your arguments have frequently been and your repeated failure to engage in honest discussion, it's gotten to the point where it's not worth wasting my time to do an in depth refutation when it passes a certain level of bad. But sure, since you're so sure that you're right....
You started off assigning others with an idiotic premise that no one was even remotely claiming or coming close to claiming -
What I think is stupid is the idea that the guns are what causes the violence in our society and that banning them, or some of them, is going to stop people from being violent.
Followed that with a related, but just as unheld premise -
Thinking that restricting guns is going to solve the problem of violence in schools or violence in general is ignoring history.
Followed that with questionably relevant information
We've passed laws against assault rifles and we still have school shootings.
Seriously, who's claimed that school shootings would just end if assault rifles were less accessible? At best, the claim related to school shootings is that fewer accessible assault rifles would tend to make school shootings less harmful on average and maybe discourage a subset of potential school shooters, not provide some magical school shooting cure.
We've passed laws against sawn off shotguns and we still have school shootings.
This one, on the other hand is just...

. I have no idea at all what you're referring to. Sawed off shotguns, at last check, are still quite legal, though some may indeed require something like registration and a background check to be legally owned. For both of these notes about laws, though, they're half-assed arguments, not least because "laws" are not necessarily either good or effective laws and because the laws weren't designed as magical cures to school shootings in the first place.
If we make the AR-15 and every other gun built on the AR-15 platform illegal, is that going to stop school shootings? If it doesn't, what do we do next?
Of course not. The intent, where it relates to assault rifles and mass shootings, in general, would be to reduce the average potential deadliness of mass shooters. That's very, very different from the intent that you're trying to claim is in play. As for what to do next? Given that there are quite a few other suggestions that have also been on the table for a while, there's plenty of potential options to work with, regardless.
I'd be interested in hearing what good things you think the NRA has been doing.
There's a lot of programs related to gun safety and gun sports that they're heavily involved in, at last check, to name a large group of quite non-controversially good things that they do.
Blaming the NRA for the actual things they've been doing is entirely fair. Blaming them for the failures at Parkland is entirely unfair.
Ehh... in a direct sense, yes. Indirectly, they've been pushing hard to change the legal and social landscape into a much more permissive shape for guns.
They don't advocate for letting mentally unstable people acquire guns.
Actions speak louder than words. They might not officially "advocate" it, and may even talk about how much they're opposed to it, but when they actively oppose just about any measures that would be able to actually prevent unstable people from acquiring guns anytime they think they can (yes, including background checks, which they lobbied hard to sabotage, in part and in full, at the same time as they officially "supported" them, then immediately and repeatedly fought against in court and with misleading or false propaganda in efforts to sabotage it), it's quite hard to take their claims seriously.
They don't advocate that law enforcement and social services ignore multiple warnings about a dangerous individual.
No, they don't. On the other hand, they push for bills to make shooting other people more generally unprosecutable with how extensive "stand your ground" laws have been made and how they're to be handled. They strongly pushed against "red flag" laws that would have given a much, much clearer and direct justification to (at least temporarily) take away Cruz's guns during a number of the times when the police were supposedly feeling like they were practically helpless to do so in that particular situation. More could likely be said, but their role is far more one of setting the stage, rather than being a direct actor on the stage.
The blame for Parkland is entirely on social services and especially the liar Sheriff Scott Israel for his failure to prevent this from happening and failure to stop it once it had.
Entirely? No. Most strongly and directly? Sure.