A month later, my understanding of trigonometric functions likewise deepened as I took over the class to learn to teach students using those same graphing calculators.

Pamela J. Wells, Understanding Linear Functions and Their Representations, Mathematics Teaching in the Middle School, Vol. 21, No. 5 (December 2015/January 2016), pp. 308-316 ...

Sam Rhodes, Jessica Duggan, Cryptic Functions: Understanding Function Identification, The Mathematics Teacher, Vol. 112, No. 2 (October 2018), pp. 108-113 ...

Unlike a linear, graph, a quadratic graph has an equation which includes an x squared term.