The nine-year compulsory education policy is a priority state policy in China. The transition to online learning caused by the COVID-19 pandemic turned out to be especially difficult for elementary school students, primarily in the organizational aspect. The need to ensure quality education and effective learning outcomes regardless of its form determined the research relevance. Thus, the "purpose" of the study is to consider the impact of the digital transformation of basic education on the development of first-graders' cognitive abilities. The study involved 205 first-grade students: 112 girls and 93 boys, their average age was 6.4 years. The experimental group consisted of three student groups (98 first-graders). The control group also involved three student groups (115 children). The null hypothesis that both online learning and traditional classroom activities have the same effect on the development of cognitive abilities in first graders was statistically confirmed.