The promises and pitfalls of universal early education

Scope of the evidence

For the evidence, the focus here is on both universal preschool programs and universal childcare programs that serve children within a few years of entering primary school (mostly aged three to five). Attention is also limited to empirical research that has made substantial progress toward estimating true causal impacts. This is a challenging condition because enrollment in such programs is voluntary, and a parent’s choice could be related to other factors that influence child development. A social experiment would sidestep the problem by removing the element of choice: by design, whether a child participates in early education is decided by the researcher to ensure that all other factors are held constant. However, it is difficult to design a social experiment to estimate the returns to participation in large-scale universal early education.

Instead, researchers have attempted to obtain variation in participation in universal early education that is “as good as” random by taking advantage of policy-imposed constraints on parental decision-making. Two policies have been central to this research. First, parents can enroll their children in universal early education only if a program exists. As a result, the difference in outcomes between children who reach the age of eligibility before the program is introduced and those who reach eligibility after it is introduced has the potential to capture the effects of attendance. Studies that use as a basis of comparison the difference in outcomes between children in the same cohorts but who are unaffected (or less affected) by the program’s introduction are said to use a “difference-in-differences” (DID) design. Second, like school systems, most universal preschool programs have entry requirements based on a child’s exact day of birth. As a result, children with birthdays right after the cutoff have to wait an entire year before they can enroll, but they are likely to be similar in characteristics to the children with birthdays right before the cutoff. Differences in the outcomes between these two groups of children one year later are thus likely to reflect preschool attendance. Studies that compare differences between these two groups use a “regression discontinuity” (RD) design.

The discussion that follows is based on a database of 34 studies of these two varieties, most of them published, spanning ten countries across Europe, North America, and South America.

An organizing framework

Theoretically, universal early education would be expected to have different impacts depending on family background. Figure 1 illustrates this prediction using a stylized graphic [2]. For simplicity, first consider a universal program that would displace maternal care or informal care that is an equivalent investment in a child’s human capital. Suppose that the quality of this program (solid gray line) does not vary with a family’s socio-economic status but that the quality of maternal care does, with mothers of a higher socio-economic status creating a higher quality learning environment for their children (light blue line). Under these conditions, the universal program would have less of an effect on the quality of learning environments for children from a higher socio-economic background. If the impacts of the program on a child’s human capital are directly proportional to the change in the quality of the learning environment (represented by the vertical distance between the light blue line and the solid gray line), universal early education would be expected to have larger effects on the human capital of disadvantaged children.

The situation becomes more complicated when a universal program could displace private or other public early education programs. In the US, for example, there is a large market for private preschool education, and public early education programs, such as Head Start, already serve many poor children. The impacts of a new universal program in this setting would depend on the relationship between socio-economic status and the quality of a child’s alternative learning environment, accounting for time spent in these other programs and their quality. Figure 1 depicts a situation where existing public early education programs have made substantial progress toward shoring up the human capital of disadvantaged children but where the quality of a child’s alternative learning environment still increases with socio-economic status (dark blue line). The same universal program would have less of an impact on children’s human capital in this situation than it would if it displaced only maternal care, but even here the impacts of universal early education should be larger for disadvantaged children.

Theoretically, the quality of the universal program should also affect the magnitude of program impacts on children’s human capital. “High-quality” early education programs are identified on the basis of process, rather than inputs, and involve interactions between children and adults that are nurturing and supportive of learning and development. Regardless of the alternative use of a child’s time, the effects should be larger for everyone the more a program achieves such “process quality,” as can be seen by comparing scenarios under the solid and dashed gray lines. Even so, there are theoretical situations in which high-quality universal programs can make a child worse off. This is a particular possibility for children from a higher socio-economic background, whose families might decide to trade off program quality for savings on private early education or care [3], [4].

To frame the discussion that follows, Figure 2 characterizes the universal programs in the database by the type of care or education they displace and by whether their primary orientation is preschool or childcare [3], [4], [5], [6], [7], [8], [9], [10], [11]. The figure also gives the target age group of each country’s program, whether the program is full day, and whether head teachers are required to have a college degree, a condition widely thought to be necessary but not sufficient for generating process quality, as defined above. Programs that have high teacher education requirements are referred to below as “high-input” or as having “high standards,” so as to make clear that they are not necessarily ones with high process quality. However, high-input programs should have a greater chance of delivering high-quality learning environments.

Figure 2 shows that, except in the US, the programs under consideration appear to substitute primarily for maternal or informal care. Among such programs, however, there are both childcare and preschool-oriented programs. In general, programs that are delivered through downward extensions of the public school system, rather than through childcare centers, appear to have higher education requirements for teachers. For example, the school-based universal preschool programs in the Netherlands and Spain require teachers to have a college degree, whereas the childcare-based programs in Denmark and Germany serving children of roughly the same age do not. Yet, there are important exceptions. For example, Norway introduced a universal childcare program in the 1970s that met many of the same standards as the school-based programs in other countries.

Short-term effects on children’s human capital

Based on the framework presented in Figure 1, universal early education would be expected to have larger positive effects on disadvantaged children, and higher-input programs would be expected to have larger impacts, provided higher inputs translate into higher process quality. These predictions have been borne out in the research. First, high-input universal early education programs have substantial positive effects on cognitive test scores, particularly for disadvantaged children. However, consistent with research on targeted early intervention [1], these test score gains appear to diminish as children progress through school. Second, though the evidence is weaker, high-input universal early education also appears to have positive impacts (that are larger for disadvantaged children) on non-cognitive skills—such as self-control, motivation, and perseverance—that are thought to be critical for generating long-term socio-economic impacts of early childhood initiatives [1]. Third, high inputs and an orientation toward preschool appear to matter for the magnitude of these short-term effects. In fact, relatively low-input programs that have a childcare orientation may not only have a lower effect; they may even make children worse off.

Longer-term impacts

Most of the programs for which there is substantial evidence on short-term effects began in the 1990s and are thus not quite mature enough to support analyses of their impacts on participants’ adult lives. The evidence on longer-term impacts of universal early education instead relies on programs introduced in the 1970s and earlier; most notably, these include universal kindergarten programs in the US and subsidized high-input early education programs in Europe (specifically, in Denmark, France, and Norway). The findings of both of these lines of inquiry can again be understood in light of the simple framework presented in Figure 1: both program quality and the quality of the “counterfactual” condition (what would have happened without the program) matter.

Owing to rich data and a fairly clean policy experiment, findings from the introduction of the Norwegian childcare program may be the most conclusive. The first cohorts to be fully eligible for the program ended up with higher levels of education and were less likely to be on welfare in their thirties than cohorts that just missed eligibility, and more so in municipalities where childcare expanded relatively rapidly. However, the impacts were larger for individuals whose mothers had low levels of education, for whom the care displaced was probably of lower quality [10]. Qualitatively similar results for educational attainment have emerged from DID studies of the Danish and French systems. The Norwegian reform also reduced earnings inequality relatively more among affected cohorts in highly-affected municipalities but did not significantly increase their earnings on average and even reduced earnings at the top of the distribution [4]. For the highest potential earners, which included children from higher-income households, the care that the program displaced was arguably developmentally more productive than the program itself, a sacrifice that parents may have been willing to make to save on childcare expenses.

Thus, the well-resourced, high-standard Norwegian program improved later-life outcomes for many children—and more so for the most disadvantaged—but it may have made children from well-off households worse off than they would otherwise have been. On the flip side, universal kindergartens introduced in the 1960s and 1970s in the southern and western parts of the US had the perverse effect of having a greater positive impact on white children than on black children. But again, the counterfactual condition may matter for this result: for a substantial share of black children, universal kindergarten appears to have displaced Head Start [9], which might have been at least as high quality as the kindergartens of that time. The positive effects (for white children only) were also smaller and less extensive in terms of outcomes than in the Norwegian case, possibly due to the lower-intensity nature of the US programs (many programs were half-day, for example) and the scope for larger differences in quality that comes with local school finance in the US.

Impacts on the family

Maternal employment is a potential mediator of the relationship between universal early education and children’s human capital. By reducing a family’s prospective childcare expenses, universal early education increases a mother’s potential take-home wage, providing an incentive to enter the labor force. Doing so can increase a family’s income, but it can also introduce new coordination problems or stressors in family life. Even programs with no impacts on maternal labor supply subsidize childcare expenses for families where mothers would already be working, freeing up that family income for spending on other goods and services, including goods and services that promote child development [3].

In general, the universal programs with larger or more broad-based impacts on maternal employment are those with less of a positive impact on children. For example, the Quebec program, which had negative impacts on children’s non-cognitive skills, had very large, broad-based impacts on maternal employment: one married mother began work for every two children who enrolled in the program [8]. At the other extreme, a RD study suggests that the pre-K programs in Georgia and Oklahoma, which had such large immediate impacts on cognitive test scores, did not draw any mothers into the labor force [11]. Likewise, the Norwegian childcare program that had such impressive long-term impacts had at most a small positive impact on maternal employment rates [10]. The maternal employment impacts of other universal preschool programs discussed above—in Argentina, Spain, and the US—generally fall somewhere in between, often with larger positive impacts for groups whose labor supply is likely restricted by a lack of affordable childcare, such as single or less educated women.

This pattern of findings might appear to suggest that, despite an increase in family income, maternal employment gains might dampen the impact of universal early education on children’s outcomes. This conclusion would be hasty, however, since a country’s decision to implement a childcare-oriented program might have been a response to high childcare demand. Nevertheless, the impacts of universal early education on maternal employment are independently interesting, since an additional motivation to invest in universal early education is to promote women’s labor force participation. The evidence suggests that these labor supply effects can be substantial, particularly for childcare-focused programs, and they can yield tax revenues to finance the program.