The successful development and implementation of this assessment involved many experts in mathematics education and many more students. Some of the key people involved with the development of the test are listed here along with their roles in the endeavor. Robert Schoen designed the content and format of the test, coordinated the feasibility study, created the scoring criteria, interpreted the results, and coordinated the writing of this report. Daniel Anderson performed the data analysis for the item calibration, exploratory factor analysis, item-response theorybased models, and vertical linking between grade levels, and he also contributed to writing the report. Claire Riddell assisted with the development and production of the test and the scoring criteria. Charity Bauduin reviewed the alignment of items with the Mathematics Florida Standards, managed the reportwriting process, and assisted with editing the style and format of the report. Amanda Tazaz coordinated the dissemination and collection of the tests and corresponding consent forms. She also provided editing and conceptual feedback for the report. Kristy Farina designed and managed the data-entry system, trained data-entry personnel on the system, verified the accuracy of the data, and assisted with description of the data-entry process and sample descriptives for the present report. Alexandra Utecht, Shelby McCrackin, Senai Tazaz, and Claire Riddell served as data-entry personnel. Claire Riddell, Mark McClure, and Monica Hurdal served as reviewers of the test items, response options, and scoring. Xiaotong Yang, Ahmet Guven, and Lanrong Li provided assistance with calculating the ICCs and R 2 estimates based on the field-test data. Anne Thistle provided valuable assistance with copy editing. We would like to acknowledge the important contributions made by the reviewers of the early drafts of the test and express our gratitude for their contributions of expertise. These reviewers include Charity