My daughter needed practice with math facts: adding and subtracting numbers from −100 to 100, and multiplying and dividing from −12 to 12. Worksheets weren't working. So we made a game in which every right answer uncovers one piece of a hidden picture, and she doesn't learn whether it's a bunny, a puppy, or a mandala until the last piece is in.
The rule that does the work
Most practice apps are designed around the right answer. The more interesting design question is what happens after a wrong one. Here, a missed question is followed by another of the same kind, with new numbers. Same operation, same signs, and for addition and subtraction the same relationship between the sizes of the two numbers, so the answer has the same sign. Guessing stops paying. That isn't because it's punished. It's because the question keeps coming back until the idea underneath it lands.
The same instinct shapes what gets asked. Question types she has been missing lately come up more often, and each answer is timed, so a fact she gets right slowly still counts as unfinished work.
What it notices
A parent's view sits behind a small Stats button. It breaks results down by operation and by sign (both positive, mixed, both negative) and lists every question type from hardest to easiest. It also puts the overall average next to a trailing one, so you can tell, rather than guess, whether practice is actually helping. Times tables get their own 13 × 13 grid, colored by accuracy or by speed. The child sees a gentler version of the same record: every so often, a note that she's faster or more accurate than her usual.
Four ways to play
The mystery picture comes in two kinds, animals or a mandala drawn fresh with new colors each time. A small virtual pet hatches from an egg and is fed, washed and played with by solving problems. Times Table Tetris drops pieces that each carry a fact, falling a little faster every few answers. Answer in time and the piece lands in the best open spot. Miss, and it falls where it is and starts to pile up.
How it was made
It is a single HTML file, written over one long conversation with Claude. I described what she needed, tried each version, and pushed back on what didn't work. What stays with me is how short the distance has become between noticing a need at the kitchen table and holding a tool built for one particular learner. That distance used to be the reason schools bought software built for the average student. I'm not sure it will be for much longer.
Play Math Magic. It’s free to use, at home or in a classroom, with no account and no sign-up. It works best on a tablet, and progress is saved only on the device you play on.