The authors present results of a study which was conducted by the Institute for development of education (Higher school of economics) in 2009-2011 years. The study was concerned with the problem of inequality in education and its aim was to find out the causes of formation of a segment of schools with persistently low educational outcomes, to develop methods and tools to diagnose their problems and deficits and to design programs which could help such schools to turn to efficient mode. The study was based on statistical analysis of data on human and material resources, children achievements and contextual characteristics of 1500 schools in three Russian regions. It also included an in-depth study of a sample of 20 schools. The focus of this study was school educational strategies. Authors used a model of «effective schools» for analysis of school education policy and strategies. The study was carried out in collaboration with the Institute of Education, University of London.