The Education Development Center's Center for Children and Technology (CCT) conducted a three year study of a large-scale data reporting system, developed by the Grow Network for New York City's Department of Education. This paper presents a framework based on two years of research exploring the intersection of decision-support technologies, educators, and the process of transforming data into knowledge. The model looks at three dimensions: (1) the process by which raw data becomes usable information; (2) the effect of the data-reporting tool in shaping that process; and (3) the role of prior knowledge of the decision-maker. The model keeps the teacher at the center of the process and supports the hypothesis that, in order, for data-driven decision-making to change teaching and learning practices, the focus of professional development should be on teaching and learning, rather than on data analysis.