Power resides in understanding it is YOU doing the choosing.
The ability to choose is the ability to exert power. As the first step on the Arc of Transcendence, the power of choice sets the stage for all future steps.
In the classroom, the power exists for you to choose some things, but not others. But, the most powerful choice, the one that matters the most is yours to make. You have the power to choose what type of students you want to be. Much of your classroom experience will come down to this choice, and your willingness to exert the power behind this choice.
How have your choices lead you to be the type of student you are?