What is the #1 rule to you makes a classroom work? Why?

          My number one rule to make a classroom work is to not to be late for class. It's because dilatory habit will cause problem to my future life. Obviously my boss in the future will not be happy about that as if now my teacher is irritated. It is the most prior engagement that I, as being a responsible person, should follow. Getting rid of dilatory habit will give the instructor a better first impression about me, in general.