Studies have highlighted the role of early Executive Functioning (EF) interventions with regard to preventing behavioral and mental health problems. In this sense, interventions to promote EF have been developed and tested; however, in Latin America, evidence of early EF-related interventions is still limited. We developed a program for EF promotion in children and applied it to first-grade students. Sixty-eight six-year-old children and their five teachers were divided into an experimental group (EG) and a control group (CG). EG teachers administered the Intervention Program for Self-regulation and Executive Functions in a classroom context. The results of the ANCOVAs showed that children in the EG had significantly better performance in measures of cognitive flexibility (Trail Making Test for Preschoolers; p = .05), attention (Cancellation Attention Test – errors in the Part 3; p = .027), inhibition (Simon Task – interference score in the part 1; p = .008 and interference reaction time in the part 2; p = .010), and planning (CHEXI – planning scale; p = .041) than those in the CG. The results show that EF can be promoted using classroom intervention in public schools. These results expand previous findings for Latin America.