The paper starts with underlying the connection between civilization changes and new demands for schools, with stating that processes of schools’ democratization and “modernization” have rather minor successes and with pointing to the fact that one the reasons of low effectiveness of such actions might be the fact of ignoring beliefs and ideologies of people on whom the reforms rely.The main aim is to uncover hidden or visible mental models of education and leadership owned by school principals and to compare it to their typical activities in order to find out if their action mirror (or not) their declared theories. It will be achieved by analyses of interviews and blogs, and also through observation of 99 school principals of primary, junior high and high schools in Poland. Theoretical and methodological framework is based on four general concepts of education (transmission, socialization, development, change) and four main paradigms of leadership (classical, transactional, visionary and organic). Finally, using variety of theoretical approaches, the usefulness of those concepts and paradigms in building democratic leadership and effective education is discussed, together with analyses of coherence between individual beliefs and conducted action or typical professional behavior.