Overview
Learning to partition shapes into equal parts is a fundamental skill for children across elementary grades. In grades K-2, children must cut / partition shapes into equal parts as a precursor to learning formally about fractions in grades 3-5. These materials are designed to be used with play-doh (or similar material purchased at the Dollar Tree).
These cutters are designed so that the whole (circle, square, or bar) is cut but the partitions are only marked (they don’t go all the way down). Children can then use a play-doh knife (such as one that can be printed here) to cut the remaining way through – thus engaging them in the partitioning task while also providing a physical scaffold.
MakerSpace Files
Cutters with Fixed Partitions
3D printer version of the files are downloadable here.
There are three models included, with each set including the whole, fourths, thirds, and fifths (children usually have little trouble learning to partition into halves).
- Circle Cutters consume 14.64 grams of filament, cost $0.26 per set (assuming $18/Kg cost) and take 40 minutes to print with a 0.6mm nozzle.
- Square Cutters consume 18.93 grams of filament, cost $0.34 per set (assuming $18/Kg cost) and take 51 minutes to print with a 0.6mm nozzle.
- Bar Cutters consume 21.11 grams of filament, cost $0.38 per set (assuming $18/Kg cost) and take 59 minutes to print with a 0.6mm nozzle.
Cutters with Moveable Partitions
The new Circle Cutters with movable partitions can be downloaded here. They consume 34.46 grams of filament, cost $0.62 per set (assuming $18/Kg cost) and take 1 hour 3 minutes to print with a 0.6mm nozzle.
Note: If you have not read the tutorial post on MakerSpace Manipulatives, please do so.
Examples of Use
Partitioning into FIVE equal parts.
Children in grades K-2 need experience cutting shapes into equal parts (equi-partitioning). Unfortunately, there are very few chances and tools to scaffold their learning to cut things into odd-numbered parts (3 and 5 equal parts). Using these play-doh cutters, children can gain experience cutting shapes into five equal parts.
After students use the cutter with the five equal parts marked, they must then use the play-doh knife to cut along the markings and make each of the five equal parts. After some time practicing with the marked cutters, children can practice cutting a circle without such markings into five equal parts.
More to come…
