There ya go!

These schools pull this horrible stuff on us because they _can_. They almost always get away with it. The teachers do little to defend themselves, trotting off to their scheduled classes like sheep no matter what the school does, or making a beeline for an airport and a ride home after the contract ends.

This is wrong. This only encourages the school to pull the same excreta on the next guy next year.

The weapons the schools fear most are the very weapons you have at your disposal. The schools hate disruption- as in cancelled classes- and they hate embarrassment- as in bad publicity.

So, if you must, next time you find your passport confiscated, call your Consulate and don't go to class. Sit in the lobby and make a scene. Same thing if you find your contract being materially violated. To either of these, let people start finding accounts of your troubles all over the internet. Keep it up until the situation is resolved. Of course, if you can get ALL the teachers at the school to hang together, this is much more effective...

We come from countries where jobs are scarce...hard-won and hard-kept. This isn't true in the EFL business in many countries, but we keep forgetting that.

By all means, be careful. Be reasonable, fair, and scrupulously honest in all your dealings with the school. Keep a mind open to compromise on the places that can be compromised and negotiated. Try to save face for your owner/manager if you can. Don't use these extreme measures lightly or often. But keep that bullet in your pocket, and use it if you have to.