The assessment of motor skills is an integral part of physical education classes with the same test for students of regular and adapted teaching program. The aim of this study is to research the metric characteristics of the tests used to evaluate motor skills of the student population in the adapted program, and to compare their results with the results of students in the regular curriculum. The sample of respondents consisted of 14 students in the adapted teaching program (experimental group P) and 14 students in the regular teaching program (control group R). The variable sample consisted of tests for assessing repetitive power, explosive power, coordination, flexibility and functional abilities. Normality of distribution was checked by using the Kolmogorov–Smirnov test (KS), while the data processing also included factor analysis, the intraclass correlation coefficient and the t-test for independent samples. The level of statistical significance is set at p<0,05. The data processing confirmed the homogeneity of the tests, which is consistent with the obtained descriptive statistics. Multiple correlation showed that there was a reduced correlation between the results of the same test between group R and group P, which underlines the fact that the validation of customized motor tests for a specific population should be considered. The results of the t-test for independent samples clearly showed a difference in the arithmetic means of all tests between the results of the studied groups. The students in R group have had better results in all tests than P group. The above-mentioned tests in schools should be modified so that they consist of an individual interpretation of a student's results, without comparison with set standards or with results of students in the regular teaching program, and including long-term monitoring of result development.