For ages I thought Ferris was an ESTP, but it never seemed right. He seemed like too strong an Se user to be ENTP but he created such a complex scheme which would have taken forever to prepare and it really just doesn't seem to fit. Then I read something about Hannibal Lecter, and how he creates such complex plans just to kill people as a result of unhealthy Se, so it gave me a thought. Maybe Ferris Bueller is actually an ENTJ with overly developed tertiary Se. He plans and builds enormous systems just to get a simple sensory thrill, a goal which most anyone would say really is not worth the immense effort. What do you think? My only issue is that he does seem to have a fair bit of Fe, but maybe that's just a skill he developed.
He looks very nonchalant in the movie, but if you think about it, that one day off would have required at least a few days of precise planning.