„Cognitive skills are a cornerstone of children’s learning, and gaps in cognitive skills emerge early. Large-scale comparative data on early cognitive skill development are scarce, but evidence from the OECD’s International Early Learning and Child Well-being Study – which examines the cognitive and social-emotional skills of 5-year-olds in three OECD countries: Estonia, England (United Kingdom), and the United States – points to significant differences across socio-economic groups in emergent literacy and numeracy skills even before children start school.“
OECD (Hrsg.), Starting unequal: How’s life for disadvantaged children (2022), S. 22.