When I teach the rules for exponents, my students can understand one lesson at a time. But by the end of the chapter, many have the rules all mixed up. The question invariably arises: “Is x2 · x3 equal to x5 or x6?” We review our discussion from earlier in the unit: x2 · x3 = (x · x) · (x · x · x) = x5. I also take advantage of this teachable moment. The properties for simplifying exponents are connected to the chart displayed on my classroom door. I have written the letters PEMDAS on colored paper and taped them up as a constant reminder of the order of operations (see fig. 1).
Patricia Wallace Gomez, Patricia.firstname.lastname@example.org, teaches finite mathematics and secondyear algebra at Dr. T. J. Owens Gilroy Early College Academy (GECA) in Gilroy, California. Her interests revolve around helping students understand the logical reasoning of mathematics and appreciate its beauty.