Curriculum reform is at the heart of educational change and impacts pupils, teachers, other educational professionals, and society at large. Moreover, the way we go about developing our schools and designing curricula defines our future and reveals where we stand regarding the role of education in society. In order to research the desired aims of reforms, it is crucial to understand curriculum making: How does the school develop, and what regulates the development? Learning is at the core of school development. It can be considered as both the aim and the primary means of achieving and sustaining any change in schools. Accordingly, the impact of a school reform is highly dependent on the quality of learning enabled within the school communities. Particularly, the extent to which the reform engages teachers in active and skillful learning by promoting their professional agency is a central determinant of the reform’s outcomes. The core curriculum is the single most influential regulator of school development in Finland. It is renewed approximately every 10 years and provides a common direction and basis for renewing school education and instruction, and sets the framework and foundation for district- and school-level curriculum development work. Teachers in Finland are curriculum makers not only in the class and school, but also at the district and even national levels of the school system. In such a system, teacher autonomy and teacher agency are at the core of school development. Moreover, teachers’ ability to understand the aims of the reform and to integrate, modify, and adopt them as part of their pedagogical practices is essential. This requires making sense of their aims. In Finland, shared sense-making has been the main strategy in the latest participatory reforms, with the aim of promoting transformative learning in professional communities in order to reach reform goals.