Spirograph
Ages: 10+
Spirographs have been a popular drawing toy since they came on the market in 1965. Typical spirographs consist of two plastic pieces. One piece is a ring with gear teeth on its inner or outer surfaces that is held stationary. The second piece is a solid shape with gear teeth on the outer surface and a series of holes inside. The gear teeth of the two pieces are aligned and a pen is inserted in one of the holes. The pen is then used to rotate the second piece to draw fun geometric designs! Different color pens can also be used to add additional flare to your designs.
The curves drawn when rotating the second piece are also mathematical curves broadly known as roulette curves. The relative size of the pieces and location of the pen in the second piece both affect the curves drawn, providing endless possibilities for designs. The spirograph built in this project operates slightly differently than the traditional spirographs described, but the resulting geometric design is very similar. Happy drawing!