You BOTH do.

Knowing that it's what your teacher wants to hear, and not seeing any way that it could go badly for you, you decide to respond.

"Who says that you can't?", you ask her.

"Hey!" she says in the same tone of voice as she's been using to lead the class, (which you're debating the affect on your attraction). "What did I say about raising your hand?!"

You hesitate only briefly, before raising your hand, and sticking two fingers into Ms. Biel's mouth.

She pauses, but then she sucks on her new present for a few seconds. Finally, she uses her own hand to remove yours, and looks down at you.

"I will have to note that you listened to my instructions, but also thought of a way to improve the situation," she admits out loud.