This could have been a good thread, except some seem to be of the opinion that since it's impossible or damn near unlikely to survive in a school bus facing a nuclear attack or attack from a trained and equipped military unit that there is simply no point in even trying to fortify against any potential scenario.
I think everyone will concede that unless you bury your bus underground and encase it in concrete, you're not gonna make a good fallout shelter out of it, and that little you do is going to protect you against a military assault. But what about the other 99.999% of things that you might encounter?
Life or death might be as simple as keeping a couple 2x4 swinging thugs out of your bus long enough to fire it up and drive off.
I used to live where it was common to have random drive by shootings into houses. I put my childrens beds so they were perpendicular to the street so that while they slept their bodies would provide the smallest possible target for a bullet to hit. Then I built headboards for their beds. They had shelves in it and stuff but it also had a "wall" consisting of 2x4's with thick plywood on either side. To top it off I always parked my vehicles right outside their bedroom wall, between them and the street. A little bit of lumber and a little bit of thought and my kids were much safer sleeping in their beds than the neighbors kids were. Never did have any drive-by's that hit my house, but I sure slept a lot better for my efforts.
So many people feel that if you're thinking about such things that you're living your life in fear and they pity you. They live in a fairy tale world where nothing bad ever happens and even if it does you can't change the outcome anyway so no point in even trying. They compare this to the make believe world of doom, gloom, goblins and bogeymen they think you live in, and they feel superior to you. The truth is that most of us have just seen the evil in some men's hearts and know what they're capable of when they think nobody is looking.
It is true that some people live in paranoid delusions and they'd be nuts even in a hardened bunker. They'd like to pretend that we're all in that category, but most people aren't like that. In my case, in the above story, the fear and sleepless nights are what prompted me to make those changes, and once I did them I never had to worry about it again.
I'm sure there are a boatload more ideas you guys could come up with to make our buses and their occupants safer should some scum-bag decide he's out to do some damage.