Derek A. Stiffler, firstname.lastname@example.org, teaches sixth-grade math at Post Oak Middle School in Spotsylvania County, Virginia. His goal is to help children develop the skills to become strong mathematical problem solvers through mathematics discovery.
Edited by Megan Kelly Murray, email@example.com, at the University of Virginia in Charlottesville; and Jane Moore, firstname.lastname@example.org, an associate professor at National Louis University in Chicago, Illinois. E-mail your insights into a student's mathematical thinking to email@example.com. Include Back Talk in the subject line. Find detailed submission guidelines for all departments at www.nctm.org/tcmdepartments.