Have your son show you how to shoot.
But know that the very first time you let a child shoot a gun, you have changed the rules forever.
It goes from dont touch, to the possibility of touch, to what they understand as a possible need to use.
Once this is done, it opens a greater possibility of chance. Kids are not always equipped to make the correct decision, add in fear, and more, and you are walking a fine line of sercumstances.
My boys were raised country, but were not ever even allowed to point play guns at other people, ever.
Even if a kid is familiar with guns, it is so easy for them to not even think that other kids are not familiar.
Though you are thinking that they need to know for thier possible safety, (and personally I agree) it is a huge can of worms you are debating, you must be sure of your learning plan, in its every detail, before you start down this path. Because 1 mistake in your plan, could easily lead to a death of your or another.
I am in no way against it, only the cautions of the possibility of a mistake.
I shot my brother when we were younger, he is fine, just shot him in the arm. we were young, We were only supose to use the gun to protect what belonged to our family. Noone was home, we were not even supose to have it out, only in case of emergency. the emergency that day was there was a dog we didnt know, trying to get in to the pigs. So we ran to the nearest gun, in the barn. By the time we got back out there (to protect family possetions) it was gone. So we did what any good boys would do, LOL, and went looking for it. (hey we didnt want it to come back when we werent looking. sounded plausable to us) well we couldnt find it so hell we figured if we shot a few times it might stay gone, hehehe. so we slung a few cans on the bank, and shot off a couple of rounds each. we knocked over the cans, so my brother went to replant them, hollering back how many holes each we had. I was holding the 22 rifle with both hands, he wanted to know where I wanted my can for a few more shots. I thought I had clicked the safety, I had shot that gun 1,000 shots, I gestured with the gun, not my hand (just pushing it forwards and saying up there) I dont even know if I finished saying that before my brother was screaming you shot me, I was still trying to figure out what happened (I knew the gun went off) there was meat missing from the inside of his arm and a graze mark on like his rib. about 3 inches or so down from his armpit. yeah it was close. Good times were over, we got that gun reloaded, and put back up double quick. Got rid of cans, lol.
Doctored up my brothers wound, and I got all our chores done, lol, mine and his. We were grown with kids before my parents ever heard that story, LOL
Kids will be kids, we were raised with a loaded gun leaned up at every door of anything we owned. House, barns, sheds. a unloaded, locked up weapon is useless on a farm. We knew better than to play with them, but that day we started down a path of resposibility, and got distracted. thats what kids do.
To teach a kid something, you need to be able to not think as a parent, with the trust that you have in them. But to think of the possibilities that the kid will think. And every parent knows that a childhood is really a series of mistakes that culminate to give the child a understanding of what they should have done. aka cause and effect. I am not saying that this will happen to yours, I am saying that parents are usually the last ones to know, that the kids they gave all thier trust to, fell short from time to time. After all they are kids.
If you plan to teach a kid about guns, your backup plan should be the imposibility for them to get to one, yes, what a quagmire. its a razors edge to walk on this one.