The Archmage (Journals of Evander Tailor #4)

If that wasn't enough, he needs to manage this while also making sure he is able to retain his job as a teacher. He's given his oath to nurture the next generation of witches and enchanters, and needs to make sure he's able to give them the best education he can.

And even if he manages to teach his students, save himself, and reveal the truth to the world, there's no way to know how the nobility is going to react...