Have you ever had chaos break out when you asked a question? Children jumping from their seats waving their hands wildly, some shouting, “I know! I know!”?
Let the children know when you begin teaching them, and remind them as often as you need to, that the first ones you call on are the ones that are sitting quietly with their hands raised. If you need to, don’t call on anyone until someone conforms to those standards. See how quickly they’ll quiet down.