I am terribly sorry to hear of this awful situation.
It is a deeply troubling state where someone who is responsible for the well-being and education of impressionable and really vulnerable people, which all children are, believes and models such blatantly discriminatory conduct.
The problem you have in dealing with this from a legal perspective is that because you are in a union the union has to represent you and must take the employer on, on your behalf, where necessary. There is no legal way for you to handle this on your own with a lawyer. In fact if you bring in your own lawyer the union will no longer be willing to help you.
But the fact is that the union does not sound like they are doing what they can for you. If they refuse to represent you fairly, which is your legal entitlement then you would bring a complaint against them for unfair representation and if you bring in your own lawyer that is how they are going to interpret your actions.
So your next step should be to go to the union and demand that they assist you. You are being made sick by the principal's actions which are mean-spirited and punitive but also, above all else, unlawful.
And give the union a letter from your employer so they can see how serious this is.
If worse comes to worse you can file a complaint with the Human Rights Commission who will take your complaint if you can show that your union cannot and will not help.
If it will make you feel better or perhaps a bit more empowered you can see your own lawyer for a face to face consultation but you should not tell the union or principal that you are doing this.
Does that help as a starting point?
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