Our interest is on historically how numbers become a preferred mode of telling the truth about schooling, teachers, pupils, and their relation to society. Numbers are here parts of communication systems whose technologies create distances from phenomena by appearing to summarize complex events and transactions. The seemingly technical appearances of the numbers enter into cultural realms that are never merely numbers but codifications and standardization of what are to constitute ‘reality’ and planning which affect several activities taking place within education. The different activities inscribe rules and standards by which experiences are classified, problems located, and procedures given to order what is ‘seen’, thought about, and acted on. We perform this task by especially discussing the role played by international, regional and national assessments in promoting a reasoning based on numbers affecting educational governance.