I have an issue with that narrative, too. Frankly, it implies that everyone will be an asshole jerk given the opportunity to do so. I don't buy that. I don't need anyone to "teach me" how to treat them. I treat everyone with respect and dignity.

Jerks, on the other hand, will get away with whatever they can. All I can do is identify them early and set firm boundaries. Not for how "they" act, but for how much I will tolerate.

I don't know what grade you teach, but if it's not kindergarten, those kids already know how they should be behaving. All you can do with the ones who don't behave appropriately is decide where the boundaries are. Yo don't "let" those kids behave that way. They choose to. Unless they're 5.