TKACHENKO, O. 2019. Research of the emotional component of first-graders’ adaptation to school as an indicator of the effectiveness of the implementation of the principles of New Ukrainian School in the educational process. EUROPEAN HUMANITIES STUDIES: State and Society. 19, 3(I) (Sep. 2019), 52–63. DOI:https://doi.org/10.38014/ehs-ss.2019.3-I.05.