This is a playable second-grade fractions game — Ohio standard 2.G.3 — built in a weekend, with no web-development degree.
The first challenge asks which cut makes two equal shares. The learner has to judge the partition, not just click through.
The next one asks them to build it — a fair cut through the center of the circle.
Then to name what they made.
Then to describe the whole in terms of its equal shares — the language the standard actually asks for.
And finally to reason: are both of these divided fairly? Recognize, build, name, explain — four strands of one standard, and the game tracks each of them separately.
Clear the level and the badge lands. The scoreboard is the part that matters for us: mastery tracked per strand, on this device, with no account and nothing leaving the machine.
The point isn't this game. The point is that the wall between “I have an idea for my class” and “it exists” has never been thinner.