American parents, how big a concern are school shootings for you?

I worry about it every time I hear about another shooting. So basically constantly.
I try to tell myself that it's unlikely, or we live in a place it couldn't possibly happen...which is all BS and I know it.
I just have to hope it's something I'll never have to deal with. If I was truly that concerned, I'd have to home school, and that's just not going to happen. So it's basically a low level of constant dread, and it's disgusting that this is where we're at here, because no one wants to face the facts and actually do anything about problem.

Not a parent, but I'll speak for my Asian-American parents.
The policy is: "You must go to school even if you have Covid, either you are buried or your are at school." (meaning: if you aren't dead, you have to go to school)
"Classmates have bullet wounds? That's your internship for being a doctor!" (/s they didn't actually say this part, obviously, but it's implied)
- "What?! You should've saved the life of at least one of your classmates so we can brag to our friends. You never think about how we feel. Useless."

I work in schools. I'm cautious about making sure side doors close behind me. That's about the extent of my shooting concerns. I've recently been complaining to security at campuses about lack of or poor fencing around playgrounds. I'm more concerned about strangers entering, kids running out, and stray dogs than shooters. Millions spent on door fobs, tracking systems, and bulletproof glass, but you can't fix a kid-sized hole in a fence? They told me the state mandated the other things; fences aren't required so the state doesn't help fund. They didn't jump on my offer of $100 and a shovel.

I wanted to comment that car crashes are probably a more common death cause for children than school shootings, and while this might still be true, apparently gun related deaths are the largest cause of death among US children with motor vehicle crashes coming in close second. Really sad considering both causes have pretty easy fixes if the government is willing to do something about it.
- The vast majority of those gun related deaths are accidents with parents' guns at home. School shootings are obviously much more prevalent here than elsewhere but they are still exceedingly rare, with perceived frequency amplified by the level of news coverage and the size of the country. I have two kids and feel strongly that parents spending any real thought worrying about school shootings (on a personal level, I mean, not a political one) is wasting their time. The cumulative effect of it probably makes schools worse
  
  The vast majority of those gun related deaths are accidents with parents’ guns at home.
  That really depend on the age of the child in question. According to the statistics as they get older it really tilts to suicide and criminal / gang violence.
  The biggest step parents can take to prevent all of it though is pretty simple; secure your firearms so that children cannot access them.
- As long as people are pointing their guns at each other instead of billionaires the government has no reason to care.
  Remember this. The job of the government isn’t to keep YOU safe. It’s to keep the people in order. They are there to prevent civil disorder. And most importantly they are there to insulate the rich from the poor.
  Working as designed.

I couldn't even stand the thought of getting used to it as a statistically insignificant threat so we emigrated. Just on general principles.
- Where to?
  
  Our only practical options were the UK and the Philippines, and we went with the UK. Pretty happy with the decision overall, even though this place has its own issues.

I live in Wyoming where even Democrats own a dozen guns and it's a matter of law that most non-felons over the age of 21 can legally carry a concealed firearm without a permit. In short firearms are prevalent and common in this part of the United States.
With that said I have almost no worry about school shootings here. The schools do a good job of securing themselves, law enforcement takes any threat seriously, and our culture understands and mostly respects firearms.
- Maybe you should turn on your local news...

A frightening but unlikely happenstance to me and mine. A lot of people experience a lot of things.
When there is a population close to half a billion, it’s a thousand times more likely that a bad traffic accident will devastate

I don't worry about it at all.
My wife would worry about it if our kids went to school in a different neighborhood, but not at the current school.

It's about the least concern.
There's a shit ton of things that are certain dangers to my kid. Plastics, toxins, climate change, political instability, and that's just the obvious ones that increase the risks of death and illness way more than the chances of some idiot kid sourcing a gun and popping off randomly with no real skill.
And, it's the risk factor a parent can do something about, directly and immediately. Home schooling is a realistic option for now. There's other ways to bypass in person education in a pinch.
It sucks. It's a problem. It just isn't even on the radar of real, demonstrable risks.

My child is 3. I’m terrified to send him. I’m scared of shootings, and I’m afraid of bullying like I faced (we’re autistic). But I also don’t want to cower in fear and homeschool him because he needs socialization, and it’s not feasible for us because I’m a single parent

Depends on what part of the country I am in. We've mostly been in New York state, half of that in NYC. In the city, guns are banned, so it is highly unlikely something is going to happen. We moved up state, and while it's in the back of my mind, I would still say it's fairly low odds. The news makes it seem like it happens all the time everywhere. Remember, it's a huge country, so it seems more likely than it really is.
Any shootings are still too many though.

Has not happened in my area but there was a parade shooting so its not like school si the only point of concern. kids get killed at school and home every so often in the city with gang violence.

Just being in the regions of multiple mass shootings over my life does change what I do with my family. If we go to an event we usually go at opening and leave early. Went to a Xmas tree lighting with 60k others and kept to the outside as the middle had nowhere to go.

Not a parent but as someone who currently attends a public school, I'm not terribly worried. Security is really tight now.
- What's being done? I've heard a bunch of news that looks more like theater than any real securiry.

Not a parent, but this is one of the reasons why.
Tbh though, not a huge reason, more of a minor contributing factor - a shooting happening at the school / specific part of the school your kid is in is pretty low odds... it's more the general state of resulting school culture and prison-like security that's damaging to the average student.
And shootings are a pretty small slice of the pie against things like the surge of popularity in Nazi shit, or our climate trending rapidly toward not supporting human life.
We've made Earth into a pretty non-ideal place to raise a child.
- Yeah. I used to substitute teach when I was unemployed. Was pretty easy process. I had to apply to the state for a certificate which was basically them verifying I had the degree I claimed from an accredited instituion. then I stopped at the high school administrative office and told the secretary I wanted to be on the list and showed my certificate and gave some preferences (I had a bs so asked for science and math but ultimately did a variety of other subjects and did enjoy them). I stopped though because now I would need to go to the district office and do a bunch of paperwork and have to pay them to do a background check and get finger printed (the state cert had a fee but it was small and one and done while every district would need its own check). The cost was such that if I susbstituted one day im not sure it would cover it. It was fine doing it but it became much more of a hassel and I could get a job quickly and end up losing money on the deal (I mean again the state cert could still lose money but it was like a super token sum. Maybe 5 or 15 dollars). Kids wear their ids around their necks now. ugh.

I doubt my child will encounter a shooter. That said, shootings are absolutely a concern. Those other kids matter too.