Bradley S. Witzel, PhD, is the Adelaide Worth Daniels Distinguished Professor of Education at Western Carolina University. Previously, he served as Distinguished Professor at Winthrop University. Prior to his academic career, Dr. Witzel was an award-winning teacher, teaching mainly math and science to high-achieving students with learning disabilities and difficulties. His work as a teacher carries through to his research, where he develops and tests mathematics interventions. Dr. Witzel has authored several books and numerous research and practitioner articles, as well as specialized manuals and multimedia works. He partners with schools and districts on matters of student learning and presents his work nationally and internationally. Dr. Witzel has served as an author/panelist for the Institute of Education Sciences RTI Math Practice Guide, an author/presenter for the Kansas Math Project, and an invited reviewer for the Final Report of the National Mathematics Advisory Panel.

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Sarah R. Powell, PhD, is Professor in the College of Education at The University of Texas at Austin. Dr. Powell started her career as a kindergarten teacher in Tennessee, and then she accidentally found her way into the world of school-based research. Currently, Dr. Powell works on several school-based research projects related to word-problem solving, mathematics vocabulary, fraction intervention, and data-based decision making. A recipient of the Presidential Early Career Award for Scientists and Engineers, she has authored over 125 journal articles related to mathematics instruction and intervention. Dr. Powell teaches undergraduate- and graduate-level mathematics methods courses, mentors doctoral students, and works with teachers nationally and internationally on the use of research-validated practices for students who experience mathematics differently. She served as an author/presenter for the Kansas Math Project.