It's a known fact that when a boss wants to get rid of someone, they make it very "unpleasant" shall we say, for the person they want out. They make it their business to completely unnerve a person and make their lives miserable. I have seen this happen in many office settings and other jobs as well.
My best advice to you is if your boss makes derogatory remarks to you, don't get upset and remain as calm as possible. Don' start taking sick days (that would be a big mistake). Make sure that you're doing what you're supposed to be doing and doing it well. Don't give him any fuel for the fire. Keep your kids out of the store.
If you can work overtime or volunteer, now would be the time, as this would be to your benefit. He just wants you to get very upset and leave abruptly and they won't have to pay any unemployment benefits. Don't give him any opportunity to criticize you.
* In the event that things can't be worked out, try to find a new job before you quit your present job.
** I wouldn't put up with this situation either, but when you answer these questions on Yahoo7, you never know the other person's exact situation. Not a healthy environment to work in at all.
In my answer I stated remain calm, which is different from quiet. I've seen this type of situation before and worked for someone like this (glad to say it's history).
As far as your kids in the store, it sounds like if he wasn't yelling about them, he'd find something else to yap about, so probably best you're not staying. Good for you.
My son and a bunch of his friends recently lost their jobs ~ and oddly enough, it's because all their bosses made the work environment quite hostile which forced them into quitting. Here in the US, if you quit your job, you aren't entitled to unemployment benefits ~ until you can prove that the boss was "out to get you" which is very tough to do.
So, in this economy, you need to keep that job and not give your boss a reason to fire you. Keep your kids out of the store (they have no business there, sorry) and be as pleasant as possible.... And for Pete's sake, don't say anything derogatory about your boss or your job to anyone since co-workers love to gossip, especially if they think it will win them points with the boss.