When the author and his colleagues last left Chicago Public Schools (CPS) and Texas' Plano Independent School District in April 2008, both school districts were immersed in the long and labored advance toward becoming a fully matured data-driven operation, one that uses sophisticated technologies to gather data, sort and interpret it, and ultimately use it to pursue actions that bear higher academic achievement. They noted then that each district was certain to "face new challenges discerning what data is relevant, addressing tolerance for change among users, and figuring out how to respond now that data is driving its decision-making." Coming back to them now, they find that in the past year both have broken through to a more developed, thoughtful, and consequential use of data by uncovering fresh ways to look at data that they had not considered before, and using technologies that allow them those capabilities. In this article, the author takes a look at how these two school districts developed their data-driven decision-making systems.