Vlad King thinks he can win a bet with Aizawa. Trading classes for a week. He's so confident they agree to put a months worth of detention supervising on the line as well as a state of the art coffee maker. Aizawa is more confident. He knows his kids are almost always batshit feral, and unruly if not given the proper care. He trained them well. But he's confident if Vlad sticks to the rules then he will at least survive the week. However when the class of 1-A learns about the bet they decide to really test Vlad king's respect not just for them but the rules. They keep their knowledge secret, they've been through a lot of hell together, not just villain attacks but personal trauma outside of their classroom. That's why the rules are there. To help them feel safe, seen, and confident.