My mother is a professor of Research Methodology in a famous B school (she has warned me not to mention the name in this blog entry...). And her class too has its share of pesky students without any exceptions. They tinker with their cell phones, read novels or news papers in class and so on. She normally pays little attention to them...or just gives them a warning if she feels their behaviour is beyond her level of tolerance.
Once in her class one Mr. Disinterested was distracting her. After having tinkered with his phone he started playing a game with his partner...the game we all have played as school children. Where you wrap all your fingers of one hand in the other and your friend hunts for the middle finger. Mom lost her cool and gave him a short and sweet warning....which resulted in a laughter riot in the class
"Excuse me...I think you and your partner may stand outside the class and find each others' middle fingers!"