This paper investigates datafication in schools through an analysis of the enactments of quality assurance and evaluation (QAE) policies in Brazil. In doing so, I question how data permeates and changes school environments, school actors' conduct and their imaginaries. QAE policies encompass large-scale assessments, indicators, rankings and other steering mechanisms, but importantly connect data to quality in education. Here, I analyse the discourses of school actors (principals, coordinators, supervisors, teachers, students and parents) from three Brazilian public schools collected through semi-structured interviews (n = 28). Data manifests in those schools as a technology of government. Schools enact QAE policies in distinct ways, incorporating the idea of governmentality, but also proposing alternative patterns of action.