Significant changes in the age structure of the population in Poland entail concrete consequences in the education system, due to the fact that either very numerous or very low number of children and teenagers go through the system. Since 1995, the number of students at various levels of education has been gradually decreasing, due to the decline in population at school age. In the field of education, determination of the perspectives and knowledge of demographic data is the basis for planning and organization of educational policy and at the lower levels – specific institutions (their number, size – opportunities and threats in the educational services market). The number of children and young people at every level of educati on is the starting point for functioning of educational institutions.