I don't know how many times I have had to hush my children so that I could finish giving directions. They are so eager and wanting to ask questions, before I have finished talking myself. They have to be taught expectations of behavior along with discipline. I think having good manners in the classroom is beneficial to everyone in the classroom and allows for the lesson to run smoothly. I feel in the long run, children who are taught manners will have a great advantage when it comes to acting and behaving around other people.
Good manners allow for good communication and also coincides with good discipline.