(1) Background: An abacus is an instrument used to perform different arithmetic operations. The objective was to analyze the benefits of mathematical calculations made with an abacus to improve the concentration, attention, memory, perceptive attitudes, and creativity cognitive abilities of primary school students. (2) Methods: A total of 65 children, aged 7-11 years (8.49 ± 1.65) participated in this randomized controlled clinical trial. The children were randomly distributed into a control group (n = 34) and experimental group (n = 31). The questionnaires used were the D2 test to measure attention and concentration, the Difference Perception Test (FACE-R) test for the perception of differences, the test of immediate auditory memory (AIM), and the test to evaluate creative intelligence (CREA). (3) Results: No significant differences were found between both groups before the intervention. Significant improvements were observed in the cognitive parameters of concentration, memory, perceptive attitudes, and creativity after the intervention, using the abacus, with respect to the control group. (4) Conclusions: It is demonstrated that a calculation program based on the use of the abacus for 8 weeks has beneficial effects on the cognitive capacities of concentration, immediate auditory memory, perceptive attitudes, and creativity. In addition, the benefits of using the abacus to improve cognitive attitudes are reported.