The story contains a boy, who loves to prank people and in general, just not follow the rules. The former principal, who was much more lenient retires and a new, stricter principal joins whom everyone hates. The boy finds something (a box or so) with his friends which (I think) he puts near or in the principal's drawer, and by the use of that box, gets body swapped with the principal.
I think it ends with both of them having a different look on their approaches to life..
The author has written more such books, and this one has a bright orange cover. It had some illustration in black and white and had quite a lot of pages (somewhere around 300-400 if not lesser). I found this book a while back and forgot about it again.