Two kids tap the same Train button. The one rated 800 gets a counting problem off an old AMC 8, the one rated 1400 gets algebra out of an AIME, and neither of them chose a difficulty or saw a problem they'd already solved. That's the whole trick, and it's the thing I wanted for my own students: I coach North South Foundation math and CheckMates chess, and a room of kids is never one difficulty level.
It's free and it's at prathammukewar.github.io/mindmasters. Parents and coaches usually want the longer explanation first.
Every AMC 8 back to 1999, every AMC 10 and 12 back to 2000, every AIME back to 1983. Official answers, the original diagrams, and a link to the AoPS solution on each problem. 13,585 of them, and not one is invented, because a made-up "AMC-style" question teaches a kid to expect the wrong thing in November.
Chess is 13,531 rated puzzles and an engine that plays a real game, so the same account does tactics on Tuesday and a full pass-and-play match on Wednesday.
Ten problems, chosen against your rating, pulled from every topic at once instead of one chapter at a time. Get one wrong and it comes back tomorrow. Math and chess each carry their own rating, the profile draws a line of every rated game you've played, and there's a streak, a daily challenge, monthly seasons, an avatar shop and a chest that only opens once the day's checklist is done. None of that is subtle. It isn't supposed to be, it's aimed at nine-year-olds.
Build an assignment, read out the code, and students paste it in. They send back a submission code when they're done, which fills in your roster, flags whoever skipped it, and shows which problem tripped the most kids. Nobody makes an account and nothing needs a connection. If you'd rather have a live leaderboard there's an optional free Firebase setup, explained inside the app. docs/ has a quick start and a one-pager you can hand to a coordinator.
index.html, MindMasters_Academy.html and sw.js are generated, so edit the part files and rebuild:
python3 assemble.py
The whole app is one HTML file with every problem, diagram and font inlined. That's the trade: a 21 MB first load, and after that it runs offline forever, off a school Chromebook with the wifi down or off a file on a USB stick.
npm i playwright && npx playwright install chromium
node test_v12.js && node test_v12b.js && node test_v13.js && node test_v17.js && node test_v18.js && node test_v20.js && node test_v21.js && node test_v22.js && node test_v23.js && node test_v24.js && node test_v25.js
Progress lives in one browser on one device. There's a backup code that carries an account somewhere else, but that's a workaround for the real fix, which is accounts that sync, and I haven't built that yet.
The bigger gap is that nobody has used this for a whole season. I know the rating picks the right problem, because I can measure that. What I don't know is whether a rating is enough to bring a kid back on a Thursday when nothing is due, and my own students are about to be the ones who tell me.
AMC and AIME problems are copyright the Mathematical Association of America and appear here for practice. Chess positions come from public game records. MIT licensed.