Purpose: The purpose of this paper is to conceptualize the implementation of educational reform processes by applying the concept of social innovation. The paper proposes a model of social innovation and test its applicability in the context of Estonian vocational education reform using two case studies of the school re-organization as an example. Design/methodology/approach: A case study approach has been applied in the empirical study. Different data collection methods have been used including semi-structured interviews with the various change actors, observations and analysis of written documents. Findings: The integrated model of social innovation proved to be a fruitful analytical tool. By focusing on five central aspects -- the trigger of change, central change agents, social mechanisms facilitating the adoption of change, implications and social gains -- it was possible to explain two school re-organization processes and the reasons behind their success or complications. Practical implications: The analysis of the cases outlined some lessons that can be learned for the future planning and implementation of school reforms. School changes are more easily adopted if actors experience it as useful and rational, school staff are involved in the process as early as possible and the adoption is facilitated by building certain social mechanisms and network structures into the policy implementation process. Originality/value: The paper makes a contribution to the literature on educational reform by applying the concept of social innovation. Up until now, the concept of social innovation has remained rather underused to explain the process of implementing and adopting reforms, and in particular, it is rarely used in the context of analyzing educational reforms.