A decade ago, many education leaders dismissed student achievement data and systematic research as having only limited utility when it came to improving schools or school systems. That was the "old stupid." But now the pendulum has swung the other way. In the "new stupid," data-based decision making and research-based practice can stand in for careful thought, serve as rationales for the same old fads, or be used to justify incoherent proposals. The "new stupid" uses data in half-baked ways, is characterized by trouble translating research, and gives short shrift to management data. Educators can steer clear of the new stupid by remembering the limitations of data, seeking out appropriate data, and applying judicious thinking. (Contains 1 endnote.)