Teaching Evolution

Hypothetical: The state passes a law requiring high school teachers to teach creationism in biology classes. You are a science teacher trained in the best scientific knowledge, you are committed to teaching truthfully to your students, and you understand creationism to be unscientific. After refusing to teach creationism because of your commitment to truth and your dedication to teaching, your principal threatens to fire you if you do not teach creationism as the state law requires. What do you do?