Classrooms, a gym and a staffroom — cases set in a building designed to keep track of where everyone is.
A corridor of classrooms, the gym, the science lab, a library, the staffroom, the head teacher’s office, a yard. Schools have the most rigid plan of any theme: rooms of near-identical size in a row, which means a clue naming a room is worth a great deal less than usual.
The regularity is the puzzle. With interchangeable classrooms, the deduction moves almost entirely to relationships and lines — direction clues, diagonal contact, distance. A small but instructive drawer: the cases here teach you to solve without leaning on room names.
A case picks its floor plan from this theme’s room pool, so the same places recur across the drawer and you learn to read them: Classroom, Assembly Hall, Gymnasium, Library, Teachers' Room, School Office, Schoolyard, Chemistry Lab, Music Hall, Canteen, Craft Room, Computer Room, Locker Room, Art Room, Hallway. No single case uses all of them — the generator and the hand-built cases alike take a subset, which is why two cases in the same setting can still feel unalike.
3 cases — 1 easy, 1 medium, 1 hard, on boards from 4×4 to 8×8. Every one is verified to have a single solution reachable by forward deduction alone, so none of them needs a guess.