Hartong, SigridSigridHartong2019-09-192013-11-1320120268-0939https://fis.uni-bamberg.de/handle/uniba/2385During the last 30 years, a new model of transnational educational governance including a specific knowledge production regime has been implemented. Its increasing national impact has caused enormous change within the German educational system. Particularly, the Organisation for Economic Co-operation and Developments statistical reports and benchmarking procedures like the Programme for International Student Assessment have challenged the German system, which has usually been remarkably resistant to reform, and have pushed it towards fast and deep transformation. Demonstrated with the case of Lower Saxony, one of Germany's largest states, effects of massive political uncertainty in terms of educational principles, rules of governance as well as school practice can be identified. They result in an increasing authorization of so-called agents of change who offer both knowledge production and education service to policy and school practice. In the case of Lower Saxony, the Bertelsmann Foundation has been such an agent of change. It supported school reform while heavily promoting the adoption of a new self-evaluation instrument called self-evaluation in schools, which not only measures school quality, but creates a new certainty by generating knowledge about what is perceived as being real within school practice. In the end, there seems to be evidence that both the teacher profession and the classroom practice are made susceptible – not only to this new reality, but also to a new leadership.engarticle10.1080/02680939.2012.672657http://www.tandfonline.com/doi/pdf/10.1080/02680939.2012.672657