The International Early Learning and Child Well-being Study (IELS) provides a rich picture of children’s early learning and development outcomes by age 5. This chapter presents the rationale for focusing on children’s skills in the early years and outlines the factors and environments that drive positive early learning and development.
Building Strong Foundations for Life
Results from the 2025 Early Learning and Child Well-being Study
Abstract
The first five years of a child’s life represent a window of opportunity, but also of vulnerability. Strong early skills promote future educational success and lifelong well-being, whereas a poor start can inhibit them. Ensuring that all children acquire the foundations for positive learning and development is one of the most efficient investments governments can make to enhance education, social and economic outcomes. Designing more effective early years policies requires a sound understanding of the timing and drivers of positive child outcomes and of their wide-ranging benefits to stimulate public investment in supporting environments.
This chapter first discusses arguments about the heightened sensibility that characterises the early years and the advantages of investments in that period. It then reviews evidence about the predictive power of early skills regarding important later outcomes in life, and concludes by outlining the main drivers of early learning and development. The chapter draws on work having informed the conceptual framework for the first two cycles of IELS (Shuey and Kankaraš, 2018[1]) (OECD, 2026[2]) and work from the OECD Starting Strong series (OECD, 2025[3]) and the OECD Centre on Well-Being, Inclusion, Sustainability and Equal Opportunity (OECD, 2021[4]).
The first five years of life are a decisive period in skill formation, and early experiences and skills can have long-lasting impacts on a range of outcomes throughout schooling and adulthood. While the importance of neurological and physical development during the prenatal period and the first two years of life has long been recognised, research in child development is also increasingly highlighting the period from 3 to 5 years of age as an equally fundamental period of child development. There is also a growing recognition of the critical role that proximal experiences and environments play for young children. The early learning and development outcomes of five-year-olds assessed in IELS reflect cumulative processes and influences over the various stages of early childhood.
An extended period of heightened sensibility
A large body of multidisciplinary research identifies the early years as a pivotal period for laying the foundations of lifelong health, learning and well-being (Institute of Medicine and National Research Council, 2000[5]). The period from conception to age two, commonly referred to as “the first 1 000 days”, is characterised by exceptional rapid development in multiple areas. These first 1 000 days, therefore, constitute a major window of developmental sensitivity, marked by both extraordinary adaptability and pronounced vulnerability. The period is sensitive in a double sense: responses to changes in the environment – both prenatal and postnatal – drive early adaptations of bodily structures, which includes the possibility that short-term defensive reactions to adversity increase the likelihood of negative implications in the long term (Moore et al., 2017[6]) (Commission des 1000 premiers jours, 2020[7]). Birth outcomes, including prematurity and low birth weight, which are often associated with maternal distress during pregnancy, constitute the first measurable markers of possible developmental and health vulnerabilities with implications across the life course (Almond, Currie and Duque, 2018[8]).
A key reason the early years are so critical for child development is brain plasticity, as depicted in stylised form in Figure 1.1. During the first years of life, the brain is at its most malleable, allowing young children to learn faster than at any other stage; however, different aspects of brain development (e.g., basic sensory processing, complex integrative functions) can peak at different times, as sensitive periods represent properties of domain-specific neural circuits rather than a feature of the overall brain (Knudsen, 2004[9]) (Stiles and Jernigan, 2010[10]).
Source: Shuey and Kankaraš (2018[1]), The power and promise of early learning, https://dx.doi.org/10.1787/f9b2e53f-en; adapted from Institute of Medicine and National Research Council (2000[5]), From Neurons to Neighborhoods: The Science of Early Childhood Development, https://doi.org/10.17226/9824.
Important complementary considerations come from growing research and policy interest in “the next 1 000 days”, defined as the period from 2 to 5 years and including the pre-school and pre-primary years (Draper et al., 2024[11]) (Nores et al., 2024[12]). Marked by accelerated growth across multiple domains, this phase constitutes another particularly sensitive developmental window in which targeted inputs can attenuate environmental risks, amplify protective factors, and consolidate adaptive developmental and behavioural trajectories. Importantly, “the next 1 000 days” offer scope to recalibrate pathways affected by earlier adversity, while also sustaining and building on achievements from the earlier period. Between the ages of 2 and 5, children undergo heightened neural maturation that supports fast growth in motor, language, and interactive abilities, as well as the emergence and gradual expansion of different aspects of self-regulation (including executive functions) that are highly experience-dependent (Draper et al., 2024[11]). This frames developmental sensitivity in early childhood as a continuing, life-course phenomenon, with ages 2 to 5 years as a critical second window where maturing learning and development capabilities remain highly responsive to both positive and adverse experiences.
A fundamental argument across these perspectives is that early foundational skills develop through relationships and context. Children’s progress toward developmental milestones depends heavily on the everyday interactions they have with parents, caregivers, and Early Childhood Education and Care (ECEC) professionals. This is because early skill development is inherently social and experience-dependent. In the first years of life, brain development is highly responsive to stimulation, especially through frequent, warm exchanges with attentive adults (Fox, Levitt and Nelson, 2010[13]). From birth, infants are drawn to social cues such as faces and voices, and they learn rapidly when adults engage them. This social orientation makes children active learners: they explore, test expectations, notice patterns, and adjust their understanding when something conflicts with what they predicted. Curiosity and experimentation are therefore core drivers of early learning, and errors should be viewed as normal signals of learning in progress (OECD, 2025[3]).
Adults play a crucial scaffolding role. Supportive caregivers help children focus attention on what matters, make sense of experiences, and, critically, develop language. Rich verbal interaction in the early years is a key pathway to later knowledge: both how much adults talk with children and how they talk (diverse vocabulary, connected sentences, encouragement, songs, and shared reading) shape learning. When parents and caregivers recognise children’s curiosity and intentionally engage in learning activities, children gain stronger foundations for later achievement (Institute of Medicine and National Research Council, 2000[5]). Besides parents’ capacity to positively support children’s development through rich interactions, children raised in stable, secure environments are more likely to develop a future-oriented mindset – including skills like anticipation and planning (Delgado et al., 2024[14]). Inversely, the experience of early adversity can speed a maturational transition from exploration to exploitation in decision-making (i.e. defaulting to known options instead of seeking new strategies), with limiting effects on learning trajectories (Frankenhuis and Gopnik, 2023[15]).
As developmental sensitivity characterises growth through the early childhood years, children’s expanding environments beyond the home context make them especially reliant on the continuity and quality of nurturing and care inputs – and not just their availability. Because development remains malleable in this period, well-timed, high-quality investments – especially in caregiving support and quality early education and care environments – can rebalance risks and protections and shift children onto healthier trajectories before school entry.
The importance of early investments
From multiple scientific perspectives, child development can be understood as a time-dependent process in which early investments generate cumulative benefits that unfold throughout childhood and into adulthood (OECD, 2021[4]). The economic approach contends that early childhood investments compound over time: early skills function as stepping-stones that accelerate and strengthen later development, making future learning and development easier, more efficient, and sustained, enabling children to master increasingly complex tasks. This dynamic view is reinforced by the concepts of self-productivity and dynamic complementarity, which explain why capabilities acquired at one stage can create dependencies across the life course in the accumulation of human and social capital (Cunha and Heckman, 2007[16]) (Conti and Heckman, 2014[17]).
The ‘Heckman curve’ hypothesis (Heckman, 2008[18]) about the rates of return of social investments in early childhood relative to later ages remains the object of intense empirical scrutiny, finding support in a range of contexts, from targeted or means-tested programmes to universalist welfare states, but most often conditional on high levels of quality in intervention design and implementation (Elango et al., 2015[19]) (Rosholm et al., 2020[20]). Evidence from randomised field experiments in both home and early education interventions further suggests that relationships between age and spill-over effects may vary between different types of skills, being generally higher for early literacy than for other areas (Fryer, 2017[21]).
Importantly, the principle of dynamic complementarity – by which children with stronger early skills would benefit more from later investments – has implications not only for the timing of investments, but also for their breadth of focus. Policies targeting multiple early developmental domains, encompassing cognitive, self-regulation and social and emotional skills, are likely to have a greater positive impact than policies with a narrower focus on skills that are likely to be addressed at later ages, and typically in compulsory levels of education (OECD, 2025[3]). A coherent sequence of skill-building interventions that spans early childhood and the first years of primary school – and is designed so that each stage builds on the previous one – can be more effective and efficient (Duncan et al., 2023[22]). Policies need also to explore avenues to scale up successful examples of multi-component interventions that address the holistic needs of young children – and, ultimately, consider the high costs of underinvestment in early childhood development (Richter et al., 2017[23]) (Nores et al., 2024[12]).
A child’s development in the first few years of life significantly predicts their later success in education, as well as their long-term happiness and well-being. Early learning and development are consistently linked to educational attainment, physical and mental health, social outcomes, employment, earnings, socio-economic status, and civic engagement. A large body of evidence combining information from the pre-school years through schooling into adulthood shows significant relationships between children’s early experiences and later outcomes (Shuey and Kankaraš, 2018[1]) (OECD, 2021[4]). The benefits of strong early learning and development are clearly evident at school entry, at the end of compulsory schooling and later in adulthood.
At the same time, no single early learning domain can reliably predict children’s later outcomes. Rather, it is a combination of early skills that support children’s positive, holistic development and well-being. While there is overlap across the major areas of early learning and development, each also has an independent effect on later outcomes. Thus, each of these dimensions is necessary but not sufficient to predict later outcomes.
Children’s well-being and happiness go hand in hand with early learning and development
There is no trade-off between early learning and children’s happiness or, from a child’s perspective, between learning and play. Happy, healthy children are active and curious and enjoy the natural processes of learning. These processes occur through interactions with family and other caregivers, and through different types of play. Through these experiences, children learn about and actively explore their world, as they also develop their foundational learning, cognitive, social and emotional, and physical skills (Zosh, Hassinger-Das and Laurie, 2022[24]). Both child-initiated free play and guided play are fundamental to children’s development, strengthening their understanding of the world and their environment. Play provides a meaningful context for learning early concepts in literacy, numeracy, and science, and it promotes curiosity, communication, and emotional involvement. Learning and play are complementary; playful learning engages children in ways that can enhance both academic achievement and social development (Hirsh-Pasek et al., 2008[25]) (Weisberg, Hirsh‐Pasek and Golinkoff, 2013[26]).
Positive interactions with others help children learn to express their feelings and preferences, listen, share, regulate their emotions, solve problems, and sustain attention and concentration. These early competencies shape how effectively children relate to peers and their ability to form friendships. For example, substantial evidence shows a positive association between emotional regulation in early childhood, early learning, and the quality of friendships and social skills developed in middle and later childhood (Blair et al., 2015[27]).
Better outcomes throughout schooling
Foundational learning skills such as emergent literacy and emergent numeracy are positively associated with later educational achievement. In addition, cognitive and emotional self-regulation, visual-motor skills and agreeableness in early childhood all predict later educational attainment. These early skills are evident in the skills students demonstrate at the end of elementary school and secondary school, including higher rates of school completion (Shuey and Kankaraš, 2018[1]). Emergent literacy and emergent numeracy are positively associated with later educational achievement (Duncan et al., 2007[28]) (Claessens, Duncan and Engel, 2009[29]) (Jordan et al., 2009[30]).
Self-regulation, visual-motor skills and agreeableness in early childhood also predict school readiness and later outcomes in schooling (Howard and Vasseleu, 2020[31]) (Robson, Allen and Howard, 2020[32]). Aspects of self-regulation, such as attentiveness and task persistence among children starting school, are positively associated with achievement in reading and mathematics throughout primary school (Li-Grining et al., 2010[33]). Children’s social and emotional skills are also related to later educational achievement. Children with emotional regulation, social competence, and coping skills at age four and five were found to have better school achievement outcomes at age eight (O’Connor et al., 2019[34]). Self-regulation appears to be particularly important for boys and for children from low-income or at-risk families in predicting later education outcomes (Washbrook, Propper and Sayal, 2013[35]).
Higher educational attainment following school
Early academic skills, such as emergent literacy and emergent numeracy, are also positively associated with educational attainment in adulthood (Schoon et al., 2015[36]). In addition, self-regulation, agreeableness, visual-motor skills, and prosocial behaviour in early childhood all predict adult educational attainment, such as completing a degree. Both self-regulation and early agreeableness have been found to be associated with higher academic attainment in adulthood, even after adjusting for earlier cognitive ability. Furthermore, early self-regulation has been found to be a stronger predictor of degree completion by age 25 than early reading or maths scores (McClelland et al., 2013[37]).
Stronger employment and socio-economic outcomes
Strong early cognitive skills, cognitive and emotional self-regulation skills and social well-being have clear positive associations with employment, income and socio-economic status in adulthood. For example, stronger verbal skills at age five are linked with a greater likelihood of being employed, higher income, higher rates of home ownership and a lower likelihood of living in social housing in adulthood (Schoon et al., 2015[36]). Similar associations are found for early numeracy and visual-motor skills.
Indeed, adults who succeeded in moving out of the poverty they experienced as children generally displayed higher cognitive skills in their early years than others from similar circumstances who remained in poverty as adults (Blanden, Gregg and Macmillan, 2007[38]).
Early cognitive skills are a stronger predictor of adult earnings for women than for men, although in a negative rather than positive direction. Women who had low early cognitive skills faced larger wage penalties in the labour market than men with similarly low levels of early cognitive skills (Parsons et al., 2011[39]). Cognitive ability in reading and math measured in kindergarten is also highly correlated with later adulthood earnings, college attendance, home ownership, and retirement savings (Chetty et al., 2011[40]).
Early self-regulation has also been found to be linked to labour market outcomes (Robson, Allen and Howard, 2020[32]). Better early self-regulation is related to a lower likelihood of unemployment, welfare dependence, including social housing, and higher income levels (Fergusson, Boden and Horwood, 2013[41]).
Better mental and physical health
Early cognitive skills, self-regulation, emotional health and social skills are all associated with better mental health in adulthood. Children with better receptive language skills at age five were more likely to have positive mental health outcomes as adults, including a lower likelihood of depression, anxiety and psychological distress. One longitudinal study found a positive relationship between participation in a specific pre-school program and long-term psychological well-being (Mondi and Reynolds, 2022[42]). Better self-regulation and visual-motor skills at age five are also associated with lower malaise in adulthood. Conversely, poor early self-regulation is associated with later psychological disorders, particularly for men (Schoon et al., 2015[36]).
Physical health in adulthood is also associated with children’s early development and skills. Early cognitive abilities, as well as self-regulation, visual-motor skills, agreeableness, and conscientiousness, are linked with adult physical health. This includes better self-reported health, better eating habits and lower likelihoods of obesity, depression and anxiety, smoking and substance abuse and symptoms of physical illness in adulthood (Schoon et al., 2015[36]) (Robson, Allen and Howard, 2020[32]).
Early learning and development and child well-being are interrelated, mutually reinforcing, and driven by the same factors. Early development is sequential and cumulative, so frequent, ongoing positive interactions lead to a virtuous cycle of skills acquisition. Human development is highly complex and characterised by the interplay rather than opposition of “nature and nurture”. Individuals’ characteristics (i.e. genetic or other biological features) are in constant interaction with their environments (e.g. features of the home and other contexts). Thus, while skills may be heritable to varying extents, the environments that children experience influence the ways in which they develop particular skills and also their potential for learning new skills (Rutter, 2006[43]) (Anreiter, Sokolowski and Sokolowski, 2017[44]).
Heightened sensitivity early in life means that young children are especially influenced by and responsive to external stimuli, such as the types of interactions they have with their parents and other caregivers. The IELS framework focuses on the family and home environments and on early care and education settings as two major drivers of children’s early learning and development outcomes, which in turn are posited to influence later outcomes (Figure 1.2).
Children thrive in caring families, where they feel safe and happy and where they are supported to learn about themselves and their social, cultural and physical environments. The day-to-day interactions and activities between young children and their parents and other family members foster children’s well-being and their emerging skills in multiple dimensions of early learning and development.
Children also learn in settings beyond their immediate home, including their wider family network, their neighbourhood community, ECEC settings, and early schooling. While ECEC/school can be beneficial for all children, they can be particularly important for children who lack strong home learning environments. For these children, experiences in early care and education may represent a particularly important opportunity to develop the key skills that will help them thrive in life.
Strong home environments provide a great start for every child
Children’s home environment is a strong predictor of children’s early development. Family socio-economic status, parental education, parenting behaviours and parental well-being all contribute to the home environment children experience and to their early learning and development outcomes (Feinstein, Duckworth and Sabates, 2008[45]).
Parents are the first to introduce children to the world. Parent-child interactions are enjoyable for both adults and infants and set in motion a positive cycle of communication. Infants form attachments to caregivers who respond promptly, warmly, and appropriately to their cues, and this sense of security supports learning (OECD, 2025[3]). The activities parents undertake with their children – such as reading together, engaging in warm and responsive interactions, and frequently using complex adult language – help create a home learning environment that supports children’s development of cognitive skills, self-regulation, social-emotional skills and overall well-being.
Source: Adapted from Shuey and Kankaraš (2018[1]), The power and promise of early learning, https://dx.doi.org/10.1787/f9b2e53f-en.
The Effective Pre-school and Primary Education Project (EPPE) identified a range of activities that parents undertake with their children that significantly affect later achievement in education, including the frequency of reading from books; playing with numbers; painting and drawing; teaching letters teaching numbers, and teaching songs, rhymes and poems, taking children on visits and creating regular opportunities for them to play with their friends at home. Home learning environments where these activities are frequent and consistent are associated with better cognitive, emotional and behavioural outcomes for young children. EPPE found the combined effect of these activities was greater than the effects of parental education and family socio-economic status, although the prevalence of these activities correlated positively with both (Sylva et al., 2004[46]).
Within home environments, young children are engaging with digital technologies at progressively earlier ages, for a wide range of purposes, often alongside their parents or under parental supervision. Evidence on the links between children’s online engagement and their well-being and development – including physical health, cognitive development and learning, and socio-emotional well-being and mental health – suggests that impacts vary substantially by type of activity and mode of engagement, rather than being associated with the total amount of time spent using digital tools. The literature further underscores the need to align digital media exposure and activities with children’s developmental stages, given that the balance of risks and opportunities changes with age. Outcomes are also shaped by personal and contextual factors that may increase vulnerability or provide protection, thereby moderating the likelihood and severity of potential effects associated with digital practices (OECD, 2023[47]) (OECD, 2025[48]).
Efforts to support children’s early learning, development and well-being are most effective when they involve supporting families to provide home environments in which their children will flourish.
High-quality ECEC and additional supports can enhance early learning and development
ECEC serves multiple functions. In many contexts, it is used as a tool to increase women’s labour participation, help families to reconcile work and family responsibilities, confront demographic challenges such as decreasing fertility rates and ageing populations, and maintain high employment-to-population ratios. More recently, however, governments increasingly view ECEC as a means of supporting children’s early development and mitigating social inequalities. Multiple factors influence whether early childhood education delivers positive outcomes for all children. These include the quality and responsiveness of ECEC provision, whether such provision focuses on the skills children need to develop most in the early years, and the timeliness and continuity of provision (OECD, 2025[3]).
Policy makers are increasingly investing in ECEC programmes to build a strong foundation for cognitive, self-regulation and social and emotional skills, especially for children from disadvantaged or immigrant backgrounds to combat the linguistic and economic disadvantages that could otherwise hinder children’s development and integration. As such, ECEC is seen by many as a critical policy measure that can promote equity, support holistic and continuous development and improve child well-being. However, research suggests that fulfilling this role rests on ensuring high and consistent levels of quality in ECEC services, with regulatory requirements governing formal ECEC provision representing necessary but not sufficient conditions (van Huizen and Plantenga, 2018[49]) (Duncan et al., 2023[22]). Further, lower levels of participation and access to lower quality services, less responsive or tailored to their needs, remain important obstacles for ECEC and early schooling to play a substantive role in mitigating inequalities (OECD, 2025[3]).
It is important to emphasise that children’s developmental contexts do not operate separately from each other (OECD, 2021[4]). The connections between home, school, and the wider community constitute “meso-systems” (Bronfenbrenner, 1986[50]) whose quality can substantially affect child well-being. Literacy development, for instance, reflects both learning opportunities in early education settings and the degree of learning support available at home. In the same way, children’s peer relationships at school are shaped by opportunities for social interaction beyond school, including interactions with friends and those available in safe and pleasant neighbourhoods.
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