Purpose: Quality management systems are being used more frequently in educational institutions, although their application has generated a certain amount of disagreement among education experts, who have at times questioned their suitability and usefulness for improving schools. The purpose of this paper is to contribute to this discussion by providing additional knowledge on the effects in educational institutions of implementing quality management systems. Specifically, this study investigates teachers' and managers' perception of the impact that quality management systems have on one essential dimension of schools, the teaching-learning processes, with impact being understood as sustained medium- and long-term organisational change. Design/methodology/approach: The responses were analysed and classified into a set of sub-dimensions linked to quality management processes in a total of 29 Spanish primary and secondary education schools that have used such systems for at least three years. Findings: The results showed that, according to the respondents, the following sub-dimensions were improving as a result of implementing quality management plans: teaching and learning processes, the analysis of student results, tutoring, consideration of attitudes and values and assessment processes. Conversely, quality management systems did not seem to have a clear impact on the teaching methodologies used by teachers or on family involvement in student learning. In fact, the perceived impact in these sub-dimensions varied among teachers of public and private schools as well as when comparing different regional autonomous communities. Originality/value: As the main objective of a school is to guarantee student learning, one of the essential purposes of school quality assurance systems is to perform all the activities aimed at ensuring high levels of student performance.