Do you know why I called you into my office? Because you have been such a bad boy! You are disturbing me and everybody else in the class. And for your bad behaviour you need to be punished. And I guarantee you that after this lesson you will never misbehave in my presence again. Now pull your pants down to your ankles, take that ruler and punish the symbol of your "manhood", your balls. Just do exactly what I say, you bad boy! Punish those balls for your own good! And for your teacher!;)