For grown-ups
SlatePals turns your child into the teacher. Smudge, a young hedgehog, works a column sum line by line in its own wobbly chalk. Exactly one line is where the working first goes wrong: forgetting to carry, taking the smaller digit from the larger, borrowing without crossing out, writing 34 as 304. Your child taps that line, picks one of three handwritten fixes, and tells Smudge the rule out loud.
The forty slips come from the classic lists of real children's arithmetic bugs. Each slip is checked by a deterministic engine, and so is every wrong option, so nothing on screen is a trick.
There is no Solve button. On the "Your sum" page your child works their own sum and each line only ever gets one of two marks: follows, or doesn't follow yet. The app never writes the answer to your child's own problem.
Whose pen? The meter shows how much of the fixing was your child's. A nudge points to where to look and costs a little of the pen; it never shows the fix.
Nothing needs handwriting recognition, an account or the internet. Progress stays in this browser. Try it at the kitchen table: write a sum with one mistake on paper and let your child find it.
What it never does
- No accounts, no ads, no tracking — anything kept stays on this device.
- No streaks, timers to beat, points to chase or leaderboards.
- No chat, and nothing anyone types is sent anywhere.