Welcome to GrID
Choose a content set, then classify its cards into three categories while keeping every Sudoku unit balanced.
How to play
- Choose a card from the card bank, then choose a cell on the board.
- Each row, column, and 3x3 box must contain exactly three cards from each of the set's three categories. In the GI regions set, for example, those categories are foregut, midgut, and hindgut.
- A completed 3x3 box receives a green rim when it contains three cards from each category.
- Row and column status boxes stay blank until full, then show a green check for a balanced distribution or a red X for an incorrect one.
- Color Key shows or hides the category colors. Hint randomly places a card-bank item correctly before correcting a card already on the board.
- Use Set to switch content sets. Switching starts a fresh puzzle.
Original publication: Dunne H, Abbott Paterson S, Spear M. "GrID (GastroIntestinal Disease): An interactive Sudoku-based clinical anatomy card game for first-year medical students." Anatomical Sciences Education. 2026;19(6):842-849. doi:10.1002/ase.70235. PMID:42130450.
Digital implementation: Micah Etter, MD.