Contemporary research on school development and improvement seems to emphasize the impact of school leaders and leadership regarding the successfulness of the everyday practices in schools. Research is focused on either identifying overall leadership practices or measuring the effect of various intangible school level variables (e.g. mission, goals, school culture, instructional climate) on student learning (Kruger, Witziers & Sleeegers 2007; Moos, Krejsler & Kofod 2008). A considerable body of research shows that school leaders have an indirect, still measurable effect on student achievement (Supovitz, Siridines & May 2010). Even if the importance of instructional leadership (i.e. school leaders direct engagement in teaching practices in the classroom), is noted, it remains a black box of school development. Surveys show that school leaders look at themselves as successful and effective in organizational management and overall instructional management (e.g. developing and assessing educational programmes) and less effective in interacting with, coaching and counseling teachers in instructional manners. Only some percents of the total amount of school leaders working time is used for direct instructional leadership, taking place in the classroom (Grissom & Loeb 2009; Spillane & Hunt 2010).

Grissom, J. A & Loeb, S. (2009). Triangulating principal effectiveness: How perspectives of parents, teachers, and assistant principals identify the central importance of managerial skills. Stanford: Institute for Research on Education Policy & Practice. Kemmis, S. & Grootenboer, P. (2008). Situating Praxis in Practice: practice architectures and the cultural, social and material conditions for practice‟. “ In S. Kemmis and T. J. Smith (eds.) Enabling Praxis: Challenges for education. Rotterdam: Sense, 37-62. Krüger, M. L., Witziers, B., & Sleegers, P. (2007). The impact of school leadership on school level factors: Validation of a causal model. School Effectiveness & School Improvement, 18 (1), 1-20. Lewis, O. & Murphy, R. (2008) New directions is school leadership. School Leadership and Management, 28 (2), 127-144. Moos, L., Krejsler, J., & Kofod, K. (2008). Successful principals: telling or selling? On the importance of context for school leadership. International Journal of Leadership in Education, 11(4), 341-352. Spillane, J. P. & Hunt, B. R. (2010). Days of their lives: a mixed-methods, descriptive analysis of the men and women at work in the principal's office. Journal of Curriculum Studies, 42 (3), 293-331. Supovitz, J., Sirinides, P., & May, H. (2010). How Principals and Peers Influence Teaching and Learning. Educational Administration Quarterly, 46 (1), 31-56.