This essay is a critical reflection on educational standardization, particularly the standardization of assessment flowing down from major international assessment projects like the OECD's Project for International Student Assessment to national and sub-national school systems. I argue that the establishment of an increasingly uniform metric to measure educational performance has developed out of the mental measurement movement from the 19th century and scientific management from the early 20th century. As this movement is articulated with commodification and neoliberalism, I use the image of an ongoing quest for a standardized educational measurement instrument similar to a thermometer or a speedometer. I call this quest the search for an edumometer and argue that it is by now well advanced and draw on Canadian examples to illustrate the argument. (Contains 8 notes.)