Jennifer M. Bay-Williams is a professor of mathematics education at the University of Louisville (Kentucky). She has co-authored numerous books for teachers and teacher leaders. Among them are Elementary and Middle School Mathematics: Teaching Developmentally (including the new Professional Development Edition) and the related Field Experience Guide, the three-volume Van de Walle Professional Mathematics Series (Teaching Student-Centered Mathematics: Grades PreK-2, Grades 3-5 and Grade 6-8), Developing Essential Understandings of Addition and Subtraction for Teaching Mathematics in Prekindergarten -Grade 2, and Math and Literature: Grades 6-8. She edited the NCTM 2012 Yearbook, Professional Collaborations in Mathematics Teaching and Learning. Jennifer has served as president of the Association of Mathematics Teacher Educators (AMTE), member of the board of directors of TODOS: Mathematics for All, member of the board of directors of the National Council of teachers of Mathematics (NCTM) and chair of the NCTM Emerging Issues Committee. She taught K-12 mathematics in Missouri and Peru. She received her doctoral and master's degrees from the University of Missouri-Columbia (Missouri) and her bachelor's degree from DePauw University (Indiana). Maggie B. McGatha is a professor of mathematics education at the University of Louisville (Kentucky). She is a former middle school mathematics teacher. She is co-author of On the Money: Math Activities to Build Financial Literacy, Grades 6-8 (NCTM, 2015). Maggie has served as president of the Kentucky Council of Teachers of Mathematics (KCTM), member of the board of directors and vice president of the Association of Mathematics Teacher Educators (AMTE), member of the Elementary Mathematics Specialist advisory board for The Brookhill Institute of Mathematics, and member of the Educational Materials Committee for the National Council of Teacher of Mathematics (NCTM). Maggie works with coaches, teacher leaders, and administrators as a training associate for Cognitive CoachingSM and an agency trainer for Adaptive Schools. She received her doctorate from Vanderbilt University (Tennessee), her master's degree from Austin Peay State University (Tennessee), and her bachelor's degree from Morehead State University (Kentucky). Beth McCord Kobett is an assistant professor of mathematics education at Stevenson University (Maryland). She is co-author of The Formative Five: Everyday Assessment Techniques for Every Math Classroom (Corwin, 2017). She is a former elementary teacher and mathematics resource teacher/specialist in Howard County public schools. She is the lead consultant on the Elementary Mathematics Specialists & Teacher Leaders (EMS&TL) Project. At the undergraduate level, Beth teaches early childhood, elementary, and middle school mathematics methods courses, as well as equity-in-education courses. At the graduate level, she teaches courses on diagnostics and interventions in education. Beth conducts professional development throughout her region, including workshops, coaching, and demonstration lessons with elementary and middle school staff. She has a particular interest in developing problem-solving dispositions in students through problem-based teaching. Beth received her doctoral and master's degrees from John Hopkins University (Maryland) and bachelor's degree from the University of Missouri-Columbia (Missouri). Jonathan A. Wray is the secondary mathematics instructional facilitator for the Howard County Public School System and has served as a member of the board of directors of the National Council of Teachers of Mathematics (NCTM). He is co-author of The Formative Five: Everyday Assessment Techniques for Every Math Classroom (Corwin, 2017). He is the president elect of the Association of Maryland Mathematics Teacher Educators (AMMTE) and served as president of the Maryland Council of Teachers of Mathematics (MCTM). A contributor to Elementary and Middle School Mathematics: Teaching Developmentally, Jon manages the Elementary Mathematics Specialists & Teacher Leaders (EMS&TL) Project. His interests include the leadership roles of mathematics coaches/specialists, teacher collaboration, effective and engaging teaching and learning strategies, strategic uses of technology, and issues related to access and equity in mathematics education. Jon received his master's in technology, and issues related to access and equity in mathematics degree from Towson University (Maryland).