Cognitive abilities are related to academic performance and professional success. Research shows that about 1-10% of individuals have outstanding cognitive abilities. Critically, theoretical and empirical criteria of assessing cognitive performance are understudied and less well understood. A measure of core cognitive performance is mental attentional capacity that reflects the number of items an individual can hold and manipulate in mind and quantitative changes in its development have been theoretically defined. We examine normative performance, as well as theoretical and empirical criteria for identifying children with outstanding cognitive performance in early grades using a classic measure of mental-attentional capacity. Children in grades 1, 2, 3, and 4 (N = 277) completed the Figural Intersection Task (FIT). Results show that normative scores from Russian speaking children closely followed theoretical expectations for all grades and were in agreement with past empirical data. Criteria for overperformance were set to be +2 and +3 above theoretical expectations and empirical scores for each age group. For this measure percentages close to those obtained in the literature were obtained using the +3 units higher than normative theoretically and empirically driven criterial. Considerations for future research and practical implications are discussed.