Measure a circle with its own parts: lay radius sticks to build the diameter, wrap diameter ribbons around the rim, and discover π ≈ 3.14 for yourself.
Children measure circles by direct manipulation — laying radius sticks rim-center-rim to see that the diameter is two radii, then wrapping diameter-length ribbons around the rim to discover that 3 and a bit fit: that bit is what makes π ≈ 3.14. Later rounds build circumferences from 3 × d plus the 0.14 bit, and a final face-off unrolls two rims to prove that longer across means longer around. The pacing fits Grades 4–6 well, or any learner meeting circle geometry for the first time.
A free, no-signup, no-ads math game for Grades 4–6 — practising circles, radius, diameter, circumference. Play in your browser on the KidsDoMath games hub or explore more Geometry & Shapes games.
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