The Head Start REDI (Research-based, Developmentally Informed) program was designed to enhance the school readiness of 4-year-old children by promoting social-emotional competencies and language development. The program involved enriched intervention classrooms that received brief lessons, hands-on activities, and specific teaching strategies linked to empirical evidence. Parents were provided with take-home materials to support skill development at home. Multi-method assessments tracked the progress of 356 children over a one-year period. Results showed significant improvements in vocabulary, emergent literacy, emotional understanding, social problem-solving, social behavior, and learning engagement for children in the intervention classrooms compared to those in the usual practice condition. The program's impact on child school readiness highlights the importance of integrating research-based practices into early childhood education programs to address socio-economic disparities and enhance educational outcomes.The Head Start REDI (Research-based, Developmentally Informed) program was designed to enhance the school readiness of 4-year-old children by promoting social-emotional competencies and language development. The program involved enriched intervention classrooms that received brief lessons, hands-on activities, and specific teaching strategies linked to empirical evidence. Parents were provided with take-home materials to support skill development at home. Multi-method assessments tracked the progress of 356 children over a one-year period. Results showed significant improvements in vocabulary, emergent literacy, emotional understanding, social problem-solving, social behavior, and learning engagement for children in the intervention classrooms compared to those in the usual practice condition. The program's impact on child school readiness highlights the importance of integrating research-based practices into early childhood education programs to address socio-economic disparities and enhance educational outcomes.