Sacha

Continuity mistake: Ferris steps out of bed and raises his arms in an 11 O'clock position to open the blinds. From the angle behind the arms are raised in a 3 O'clock position.

Sacha

Continuity mistake: After Ferris plays with the synthesizer, the principal is fidgeting with some pages. The way they're folded changes between angles.

Sacha

Continuity mistake: When the movie starts and Ferris' parents leave the room, his right arm swaps from being over the blanket to under, between frames.

Sacha

Continuity mistake: When the opening credits are rolling, Jenny shows up in the bedroom and Ferris's hair keeps swapping from messy to brushed back and forth.

Sacha