EN
The main topic of the paper is concentrated on the quality of school achievements in language and mathematics of 9-year olds-completing the first stage of primary education and the possibilities to use analysis of results as an instrument of increasing the quality of elementary education. OBUT was conducted in 2011 and 2012 among the majority of Polish primary schools. The main goal of research was enrichment of knowledge on effectiveness of school education which complete teachers’ everyday observations and activities. The results of research OBUT was treated as an element of school evaluation. In the paper is presented the methodology of research, especially the procedure of preparation and carry out of nationwide research at schools, the role of teachers during the process of completing and coding the data and the role of reports from research. The last part of the paper includes the critical analysis and discussion concerning the purposefulness of this kind of research , interpretation of results and possibilities and limitations of implementation recommendations from reports at elementary education.