In this article, diagnostic tasks were selected based on evaluation criteria for primary school age children with SEN, on the basis of which an assessment of special educational needs was carried out. As a result, differences were revealed between two groups of children "children who have passed the assessment of PMPC" and "children who have passed the assessment at school". To determine the evaluation criteria, we examined the legislative system and features of the evaluation system of a number of foreign countries with a developed system of inclusive education, in particular the United States and Great Britain, from their official education website. Diagnostic tasks were selected according to the same criteria and an experiment was conducted in secondary schools. The aim of the experiment is to clarify the criteria for assessing primary school-age SEN , created diagnostic tasks and determine the possibility of using the information received from them in the educational process to improve the effectiveness of teaching children with SEN.The result of our study was calculated according to the methods of mathematical statistics, in particular according to the Kolmogorov-Smirnov criterion, and the comparison of the two groups was calculated according to the T-Wilcoxon criterion." Based on this study, recommendations were developed on the use of the evaluation results of children with SEN in the planning of the educational process. It is adapted for use in educational institutions.