Background: environmental influences in the first years of life have a great impact on adulthood. Adequate environmental stimulation in the first years of life positively influence cognitive, emotional and neurological development. Studies show that high quality education for 3 to 6 years old children are cost-effective for diverse outcomes, such as socioemotional and cognitive development, as well as school performance. However, it is not clear why specific types of interventions are most effective on school readiness, an important precursor of literacy status and later life outcomes. Objectives: adapt to the Brazilian context two well-known intervention programs: (1) executive functions training developed by Diamond, and (2) oral language skills based on the Nuffield Programme developed by Snowling and colleagues. Methods: a randomized controlled trial involving 720 children (4 to 5 years old) allocated to three groups: (1) adapted school curriculum focusing on executive functions training, (2) adapted school curriculum focusing on oral language skills training, and (3) regular school curriculum.

Inclusion Criteria:

• Schools interested in the intervention program
• Preschool children (4 to 6 years old)

Exclusion Criteria:

• Presence of any sensory impairment
• Intellectual disability