Drag the sector handles around a ticked rim so the spinner's sector shares match a target probability, predict counts for N spins, and rebuild a model from observed frequencies.
The spinner's rim is divided into equal ticks, and the player drags the sector boundaries so each colour's share of the rim matches a target probability given as a fraction, percent, or decimal — equal sectors make a uniform model, unequal ones a non-uniform model. Predict rounds ask for the expected count in N spins (P × N) and then run the trials so predicted and observed can be compared; model rounds reverse the process, resizing sectors to fit recorded frequencies. It targets the misconception that a probability is a count rather than a share of the whole, and that observed results should match prediction exactly. Best for Grade 7.
A free, no-signup, no-ads math game for Grade 7 — practising probability, probability-models, relative-frequency, expected-value, uniform-vs-nonuniform. Play in your browser on the KidsDoMath games hub or explore more Data & Probability games.
By grade level: 7th Grade Math Games
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What math does Spinner Designer practice? Spinner Designer practices Probability, Probability Models, Relative Frequency, Expected Value. The spinner's rim is divided into equal ticks, and the player drags the sector boundaries so each colour's share of the rim matches a target probability given as a fraction, percent, or decimal — equal sectors make a uniform model, unequal ones a non-uniform model.
What grade is Spinner Designer for? Spinner Designer is built for Grade 7 (ages 12–13). It sits in the Data & Probability strand, and it ramps across 8 levels so younger or older players find their own pace.
How do you play Spinner Designer? Drag the sector handles around a ticked rim so the spinner's sector shares match a target probability, predict counts for N spins, and rebuild a model from observed frequencies.
Is Spinner Designer free to play? Yes. Spinner Designer is free, with no ads and no sign-up, and it runs in the browser on a phone, tablet or computer.