A web app for 3rd and 4th graders to practice multi-digit multiplication on a place-value grid.
- Type a problem from your workbook (e.g.
364 × 57) or generate a random one. - The grid sets itself up automatically: place-value columns, carry-over rows, partial-product rows, and a final sum row, all aligned.
- Hints catch the common mistakes (swapping the carry and ones digit, adding instead of multiplying, multiplying instead of adding) and explain the next step.
- Once the multiplication is correct, the answer digits turn green as the child enters them in the bottom row.
It's a static site — just open index.html in a browser, or serve the directory with any static file server:
python3 -m http.server 8123Then visit http://localhost:8123.
- Open the hosted URL in Safari.
- Tap the Share button → Add to Home Screen.
- The app launches fullscreen from the Home Screen with its own icon.
Plain HTML, CSS, and JavaScript — no build step, no dependencies. The grid is laid out with CSS Grid; state is kept in memory and persisted to localStorage (current problem and solved count).
Source PNG is in icons/ along with the resize script (make_icons.py) that generates the various sizes referenced by manifest.json and apple-touch-icon.