My advice is to move on. Don't dwell on this because you aren't going to change it. Jobs don't work out for a variety of reasons. Sometimes you can do your best and still get treated unfairly. There's probably more here than meets the eye, more than a $25 camp fee, and more than the health, safety and welfare of the students. Pick yourself up, dust yourself off, and, if so inclined, get hooked up with another program. There are always teams and clubs looking for help. And losing your job doesn't take away your "good name" or the good you've done.

The best you can do is learn from this event. Ask yourself what led to this and what you could have done differently had you known what others were thinking. Even if you think you were "right" and others "wrong" you can still benefit from trying to see the situation through the administrator's eyes.

I got passed over once for a promotion and felt I was treated poorly so I quit. Turned out that not getting promoted was the best thing that ever happened to me.

And lastly, even though you might feel angry now, resist the urge to bad mouth those you think abused you. That will say more about your character than anything else you can do in the short term.