Chaz and the study group

"Why have you bought a tiny chalkboard? The room already has a whiteboard that we can use."

"I just thought we could put a do not disturb sign outside, just so that we don't have to interrupt the study session every ten minutes because someone wanders in thinking it's an empty class."

"You know Chaz, if people actually bothered to read things before entering this classroom, they would know we booked it from the calendar that ALREADY EXISTS!"

"So what, you want me to waste this twenty dollars? I have bought it and I'm going to use it!"

Chaz smiled one of his charming smiles. He and Piper had fifteen minutes before the other four members of their study group would arrive. They usually arrived early to set up. Piper was always the lead in the study session and she liked to be prepared on the arguments, while Chaz was only there to carry his friend's books and so that he could always make a point to be on time, being the one who organized the group.

He looked down at the small chalkboard and the assortment of colored crayons that came with it. "Fine, I'm not gonna write Do not disturb, but I will write something!"

The question was... what?