Extensible Arithmetic Spinner, Math Spinner, Math Wand, Snap Spinner

thingiverse

Arithmetic Spinner, Math Spinner, Math Wand, Snap Spinner, Extensible Update: Added a slightly loose version with reinforced connectors. Also added chamfer to connectors to the regular version. Please try the loose version first. The math spinner does not teach. However, it might motivate children to think about mathematics and ask questions such as “What does that mod thing do?” or “Is it okay if I say 5 + 3 > -20?” It could be used as a random problem poser. Children like problems that are tangible. Using snapping structures, I have figured out a way to make an extensible arithmetic spinner or math wand. There are four types of rings, each of which is 25mm in diameter at the interior circle and 35mm at the outside and 10mm wide: 1. Digits (0-9), 2. Arithmetic operators( +, -, ×, ÷, mod). Modular arithmetic is an important idea. It simply means keeping the remainder. For example, 15 mod 7 = 1 . 3. Relational operators (=, ≠, <, ≤, >, ≥) 4. Signs (+, -, blank/unsigned) 5. Cap 1, optional. 6. Cap 2, optional. One can print multiple sets, mix and match, and create very long number sentences such as ### × ## = ##### or ## × # + # = ###. The end caps are optional. Please be very careful not to hurt fingers when snapping rings together. Gloves are recommended. To remove a ring after assembly, please use a flat-end screw driver and slowly pry it off. Have fun and help kids do some math!