Dreams of a principal denote your issues with authority.
If you dream that you are the principal, then this dream reflects the way you handle your power and responsibility.
If you dream of being in a weaker position beneath the principal, then this dream is about how you struggle for power, rebel, or learn from someone in a higher position. This dream could be wordplay, giving you the message to connect with your higher principles.... Strangest Dream Explanations
If you dream in getting in trouble with the school principal, you may have guilty feelings about something you have done in real life. Have you done the right thing in a certain situation?... My Dream Interpretation
Being sent to the principal’s office may express worry and concern about your behavior or fear of punishment by an outside authority. It may also represent repressed childhood anxiety.... Ariadne's Book of Dream