1d, 2d, 3d! Starring Pi, Radius, Curcumference and Arc

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Create circle structures using snap hinges with interchangeable sections in radii of 1, 2, 3, or 4 units, maintaining same area and volume regardless of size. Assemble enough sections together (equal to radius squared) for a circular shape or extend them lengthwise to determine circumference. Vertical wedges also snap into place, forming volumes. Test the theory using hollow wedges filled with sand/water to confirm pi-based measurements. To print, export Autocad object as STL in makerware on Replicator 2; use supports and omit rafts, with four walls and 20% infill. Lesson effectiveness depends on consistent radius scaling (inches or centimeters). Infill sizes affect handling and production time; c-clips provide better latching while ball and socket hinges ease support cleanup. Hollow wedges are included for volume measurement proofs.