Loree Silvis is an experienced primary-grade teacher who left the classroom several years ago to delve deeply into the cognitive research on how young children construct an understanding of important foundational mathematics concepts. In support of early educators, she led the development of several graduate level courses which focus on number, additive reasoning, problem solving and foundations for algebraic reasoning and facilitates these courses throughout Vermont. She also co-led the development of the Primary Number and Operation Assessment (PNOA) with support from the Vermont Agency of Education and continues to work with districts in the development of comprehensive assessment systems and in the implementation of the Common Core State Standards for Mathematics in the primary and elementary levels. Loree Silvis can be contacted at Cornerstone Mathematics Consulting, 1519 Notch Road, Bolton, VT, 05465, 802-434-5080, or lsilvis@cornerstonemathematics.com.