Hat tip to Jim Olsen and John Golden: Best spirograph app ever. http://t.co/lejJ7TQXw9 Thanks for the tip @DrOlsen314! — John Golden (@mathhombre) November 6, 2014 Great activity for kids (and adults) of many levels: How many rotations until the loop is closed?


Fantastic. Spirograph – @GeoGebra Tube http://t.co/psD72mnc full frontal trochoid features. Maybe purges the obsession. — John Golden (@mathhombre) February 6, 2013 Questions for students: What’s with that fraction on the left side? What does that do? How do I get a graph with 7 “arms”? What is a the graph with 2 arms called? How […]