Hello and Welcome!

I'm a mathematics professor at American River College in Sacramento. A few years ago, I came across Michael Hartl's Tau Manifesto and found the arguments for using tau over pi compelling. As an educator, I was particularly intrigued by the tutoring experience of an anonymous MIT undergraduate whose younger sister was having difficulty with high school trigonometry. The anonymous student indicated that using tau rather than pi for radian measure was a turning point in the sister's understanding of trigonometry.

Does the use of tau help students acquire trigonometry concepts? It is an open educational question. I wanted to find out for myself. Being scheduled to teach College Trigonometry in Spring 2015, I decided to experiment and use tau rather than pi. There weren't many resources available to me so I had to modify and create my own. The purpose of this website is to share the resources that I've found and created so that other faculty can experiment with tau in their trigonometry classrooms. Please feel free to use these resources. And if you find/create additional ones and would like to share them, please let me know so that I can add them to this website.

I hope the website is useful to you and your students!


Phil A. Smith

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