Teachers, save “Innovative activity: Harmonograph” to assign it to your class.

A harmonograph is a drawing machine powered by the freedom of motion. It draws endless attractive geometric designs and patterns, in other words, harmonograms, using nothing but swinging pendulums, an oscillating pencil or pen, and 3–4 minutes. Making a harmonograph is one of my favorite projects to do with my students, especially those who are interested in design and engineering. Working on a harmonograph project with students is a fascinating process. It’s a great project to display science & engineering. For instance, while the pendulums are moving and pen/pencil is oscillating, you can see that the energy is transferred between the pen/pencil and the pendulum. You can also figure out the mathematics of a harmonograph