Steven J. Leinwand is a Principal Research Analyst at the American Institutes for Research in Washington, DC, and has held leadership positions in mathematics education for more than 30 years. He is past president of the National Council of Supervisors of Mathematics, served on the NCTM Board of Directors, and was a mathematics consultant for the Connecticut State Department of Education. Author of GO Math!, he provided insight for the assessments. He is also the author of numerous articles, books, and textbooks and has made countless presentations with topics including student achievement, reasoning, effective assessment, and successful implementation of standards. In 2015, Steven Leinwand received the NCTM Ross Taylor/Glenn Gilbert National Mathematics Education Leadership Award.