The most disruptive part of teaching is the student that comes in late or return late from a break. I talk to the students in private and advise them that this type of conduct in the work force will cause several actions to occur. 1st time you will be written up, 2nd time you will be placed on non pay for a certain amount of time, and the 3rd time you will be fired. I also stress the fact that numerous others in the workforce are waiting for your job.
Like everything in life this method only works part of the time, not always.