Basics · 5 minA sudoku where you draw the boxesNumber Islands keeps sudoku's famous rule but hides the boxes. Here's how it works, and why that one change makes such a satisfying puzzle.
History · 6 minFrom Euler's 36 officers to Number IslandsA 6×6 grid has puzzled mathematicians for nearly 250 years. A short history of Latin squares, Number Place, sudoku and its shape-shifting cousins.
Strategy · 7 minSix moves every island charter should knowThe same handful of ideas solves almost every Number Islands puzzle. Learn to spot them and the hard levels start to fall.
Walkthrough · 8 minSolving First Landfall, step by stepA complete walkthrough of Printable No. 01: every coastline, bridge and number, with the reason each one must be true.
For teachers · 6 minNumber Islands in the classroomA free, ready-to-print activity for logical reasoning. Here's how teachers and parents can run a 30-minute session.
Community · 5 minClubs, championships and communities for puzzle loversIs there a club for this kind of sudoku? Not one just for Number Islands yet, but a lively world of variant-sudoku fans is waiting.