Episode #3.6 - S3-E6
Continuity mistake: When the kids are strategising Harvey takes a drink of water out of his glass leaving barely anything in it. A couple of shots later and his glass is almost half full somehow. (00:04:48)

Starring: Terrence Hardiman, Frances Amey, Gunnar Cauthery, Thomas Szekeres
Episode #3.6 - S3-E6
Continuity mistake: When the kids are strategising Harvey takes a drink of water out of his glass leaving barely anything in it. A couple of shots later and his glass is almost half full somehow. (00:04:48)
Episode #1.1 - S1-E1
Visible crew/equipment: When Lloyd and Harvey are studying in the library (just before Harvey says "what do you think they're doing?") the boom microphone drops down into the frame above Lloyd's head. (00:14:17)
Trivia: "The Demon Headmaster" is actually only a Headmaster for the first three episodes of Series 1.