The school is in the social, cultural and political contest which is complexical and changeable. Our society’s democratization and education reforms obligate us to look at the education aspects newly. One of them is the students abilities’ diagnostic. There are talking about mathematical abilities in this work. But, of course, such diagnostic principles can be used in other subjects, too. The main education’s mission is to develop the person’s forces, to formulate a human for the life in the society which is changing very fast in the sociocultural condition. The training is becoming orientated into the process but not into the results. But it’s very important to reach positive changes in each student’s studies. So, it’s very important to know every pupil, to understand his/her person’s features, addictions and faculties. The primary school had refused to value students’ knowledge and abilities in marks. But after some time there had risen necessity to create a new estimation system, which can mach purposes and goals in the training. The teachers need objective and reliable estimation’s instrument. Such instrument can be the standardized learning gains’ tests. There are talking about the tests’ information (which is necessary), perfection, administration, the forthcoming results’ interpretation in this work. The subject of the research is primary class pupils’ mathematical abilities as the diagnostic construct. The aim of the research is to open methodological, theoretical... [to full text]