Teacher and student sorting within and between schools has historically garnered national attention and controversy. Scholars have recently examined how school leaders make data-driven decisions to create more equitable schools, particularly through teacher and student assignment practices. School leaders use student test scores to strategically sort students into classes to create "balance." Student achievement data is also linked to teacher reassignment, in which ineffective teachers are strategically reassigned to non-tested grades or subjects, while effective teachers may be promoted to leadership positions. Scholars have found that a combination of data-driven strategic staffing, accountability pressures, and micro-politics are prime drivers of assignment strategies within schools. Within the literature on assignment practices, one strand examines the impact of assignment practices on students but does not engage with principals' decision-making strategies despite the central role principals play in school decisions. The second strand of research delves deeply into leadership decision making but seldom provides data on the actual assignment practices. This includes observed data regarding the two types of assignment strategies dominant within the literature: privilege- and learning-centric. A learning-centric assignment is the placement of highly knowledgeable teachers with students who need effective teachers more than do other peers (Donaldson, 2011, In contrast, privilege-centric assignments place experienced teachers in classrooms with higher achieving students. School leaders may also use privilege-centric staffing to appease affluent parents and increase retention of their more experienced teachers. Although privilege-centric assignments may be counterproductive to the student experience, many schools employ this strategy despite principals' reports of using data to increase school equitability. The assignment of teachers to students and classes is presumed to be an entirely local (school-level) decision, with school leaders having substantial authority over this process. The findings of the preceding research underscore the importance of principals in this process, and yet we know little about the ability of leadership to interrupt systems of privilege and institute more equitable staffing arrangements. Because of this potential inconsistency between principals reporting that they make data-driven decisions and their actual assignment practices, we see the need for continued research in this area. The purpose of this study is to fill this gap within the literature by first examining the relationship between principals' reported data-driven decisions and teacher and student assignment strategies within schools, and then looking at the relationship between assignment practices and student learning. This study couples survey data from 213 Florida elementary and middle schools with 8 years of longitudinal, statewide data to address the following questions: (1) To what extent are privilege- and learning-centric assignment practices used within schools? Are these practices changing over time?; (2) How do privilege- and learning-centric assignments impact student-learning gains?; (3) What drives student-assignment practices--is this phenomenon embedded in the culture of a school or do principals dictate assignment practices?; and (4) How are principals' reported uses of data related to observed privilege- and learning-centric sorting?