

In a liquidation sale, common stock holders only get paid if there is money left over after everyone else gets their cut. Creditors, bondholders and preferred stock holders are ahead of them in line.
It’s also worth pointing out that the company is not publicly traded, it’s privately owned, so in effect the shares were always worthless. It’s not clear to me if they were actually ownership shares or just options against the possibility of the company going public at some point in the future.
Most teachers are amazing people that I trust completely. I still don’t want them to be carrying guns around my kids. For one, there’s always the remote possibility that the teacher flips out and uses it in anger on a student or another faculty. Secondly there’s the possibility that a student gets their hands on it. The bad things that might happen are far more likely than the slim chance of an active shooter showing up and a teacher actually being able to stop them.