As a teacher, our boss is the vice-principal and the principal. Although it is unlikely we will lose our job over enforcing boundaries with our boss, it is also good be pick the battles we want to fight.
If the principal is asking us to do something that is part of our job and in the collective agreement, we need to do it. If the principal is asking us to do something is not part of our job and not in the collective agreement, we don’t need to do it, however we may choose to do it. Life can be a lot easier when we are on the principal’s good side, so whenever possible, I do these things as well.
If the principal has asked me to do something that I am not going to do, I let them know why and I try to come up with another solution to solve their problem. Often with some discussion, we can come up with a solution that is good for everyone.
When no solution can be found and the principal is still insisting, it is time to get your union rep involved. This is a big step, so do consider if this is a battle worth fighting.
When the issue continues to be a problem even after the union rep is involved, it may be time to change schools. Alternatively, principals move around every few years, you may just want to wait it out.