Hi HN. I built a free math academy that's structured as a tour of duty in a fictional Martian navy.
Every gamified math app I tried (and I tried a lot with my own kids) answers "what's next?" but never "why am I doing this right now?" Streaks and XP are habit engineering bolted onto worksheets. I wanted the math to be in the story.
So here the curriculum IS the narrative. You enlist as a Recruit. To earn your promotion you rearrange equations, and your answer goes on the maintenance ticket. Later you solve a system of equations to bring two ships together in a docking corridor, and a flight control either accepts your worksheet (or doesn't). Progress is military rank - 20 grades, Recruit to "Voidmaster", each with a posting, an insignia, and a promotion ceremony.
What's live today: all of Tier 1 and Tier 2 — 41 lessons and 6 multi-stage missions, from arithmetic through all of Algebra I (functions, graphing, quadratics, the quadratic formula, combinatorics, induction). It's charted out to calculus, linear algebra, and orbital mechanics. Everything is free; there's no paywall — locked content just means you haven't earned the rank yet.
The math is real and I am trying to keep it as close to an imagined real Martian environment as possible.
You can play the first lesson right now with no account. Enlisting (one tap with Google) only matters once you want to save progress and start earning rank.
Thanks for looking.