The period consolidates an ecological and psychosocial approach to early childhood education, foregrounding how family, school, and community contexts shape development and learning. It elevates play as a central mechanism for cognitive and social growth, leading to curricula that emphasize exploration, hands-on learning, and social interaction. It expands attention to children's self-perceived competencies and peer relations, guiding classroom practices that foster secure relationships, consistent routines, and adaptive support across transitions. Historical Significance: The synthesis anchors a holistic view of development within cultural and institutional ecosystems, influencing curricula, policy, and program design well beyond preschool. It introduces reliable, age-appropriate measures to assess perceived competence and social acceptance, enabling targeted early interventions. Through reframing attachment and representation, it shaped educational environments that prioritize secure relationships as foundations for long-term learning, resilience, and healthy social development.