Wolfoo Grid Garden is a free Shikaku-style logic puzzle: a few numbers are scattered across a square grid, and you drag one finger to draw rectangular beds so that each bed contains exactly one number and exactly that many squares. When the beds cover the whole grid without overlapping, everything bursts into flower. No timer and no losing — a wrong rectangle just flashes red so kids can redraw it. A hint button and a 3-star rating encourage solving it unaided. Safe for kids 5-10, right in your browser.
Shikaku is about the most natural way to put multiplication into a game without kids noticing they are learning: to draw a 12-square bed they have to think of 12 as 3×4, 2×6 or 1×12 — then look at the grid to see which fits. That is factorisation learned by hand rather than from a times table. It also trains elimination: once one bed is settled, the neighbouring one often has only one possible shape. No timer, no losing, mistakes only flash red. Free, inside the parent-controlled Wolfoo environment.