The aim of this thesis is to verify the practical utility of the Application of Cognitive Functions Scale (ACFS) to determin cognitive development of pre-school children. The theoretical part looks into specifics of the pre-school period and introduces the precise meaning of dynamic assessment, which is typical by its format consisting of three phases: pre- test - intervention - post-test. This part outlines the ACFS method and the influence of an adult on the process of mediated learning experience, which is a vital part of the intervention phase of the dynamic assessment. The empirical part describes the use of dynamic assessment and examines the possibilities of the ACFS method to observe the potential of cognitive functions development of pre-school children. The results show that the ACFS method is well-adapted to identify the potential of cognitive functions development of children and it provides specific and efficient guidelines for further development of their cognitive skills. Keywords: pre-school period, dynamic assessment, mediated learning experience, ACSF method, cognitive development of children