A running start

IN 1965 Lyndon Johnson introduced “Head Start” as part of his “War on Poverty”. Conceived as an intensive summer school for poor three- and four-year-olds, the programme now serves almost 1m children a year, all year round. That still leaves roughly half of American children of that age receiving no formal schooling at all, compared with just 10% or less in much of industrialised Europe and Asia—an imbalance politicians on the left, including Hillary Clinton, are eager to address. Not before time: research on early-childhood education suggests it is a smart investment.

By the time pupils begin primary school, there is a huge gap in achievement between rich and poor. In a 2011 paper Sean Reardon of Stanford University examined the difference in test scores in maths and reading between children from families in the 90th percentile of the income distribution and those in the 10th. He found that at age six it was already greater than one standard deviation and had barely diminished by the age of 18, leaving it equivalent to several extra years of secondary schooling. The gap was twice that between black and white students, and growing.

Research by Meredith Phillips of the University of California, Los Angeles, suggests that is because wealthier families are, in effect, home schooling their children. By the age of six, she estimates, children of wealthy parents have spent as much as 1,300 more hours in enriching activities than those of poorer families. Poorer parents are strapped for money and time; roughly 35% of children in America live in single-parent homes.

Proponents argue that good public pre-schooling would therefore be a social and economic boon. It would boost social mobility, they say, while also saving public money in the long run by reducing the need for remedial education, poverty assistance, state-funded health care and the like. The effectiveness of public pre-school education has long been a subject of debate, however. Head Start, for instance, has not prevented the divergence in fortunes between rich children and poor. Studies of preschools for the disadvantaged have often established only a passing improvement in test scores.

The value of pre-school has become clearer in recent years as participants in several long-run studies have grown into adulthood. The Perry Pre-school Project, for instance, divided 123 children in Michigan in the early 1960s into treatment and control groups, and then tracked their performance as they aged. A similar programme initiated in North Carolina in the 1970s tested the impact of pre-schooling on 111 children, again divided into a test and a control group. Although pupils’ early advantage on measures of cognitive ability eventually erodes, participants nonetheless fare much better than peers over the long run. The high-school graduation rate among girls in the Perry Project who had attended pre-school, for instance, was 52 percentage points higher than that of the control group. Preschoolers from both studies were more likely to be employed as adults and to earn higher wages. They were also healthier, less likely to smoke and less likely to be arrested.

By the same token, a paper published in 2014 by Pedro Carneiro, of University College London, and Rita Ginja, of Uppsala University in Sweden, uses local-level shifts in the eligibility criteria for Head Start to tease out the links between participation in the programme and local socioeconomic trends. Head Start was associated with lower rates of obesity and smoking, reduced incidence of depression and less time spent in prison.

Such studies imply that pre-schooling is providing more than a good grounding in finger-painting, or even an early exposure to letters and numbers. Proponents argue that intensive, hands-on programmes help children develop important habits, such as conscientiousness, which do not show up on tests but are clearly useful later in life. The successful cultivation of such skills makes early-childhood education a particularly good investment, because it enables those who receive it to capitalise on subsequent instruction in education or work training, for example. Indeed, one study estimates that spending on pre-schooling for poor children yields a return of 7-10% a year in terms of longer life expectancy, higher earnings, lower crime and reduced public spending.

One for all

Whether governments should provide pre-schooling for all is a trickier question. An expansion of free nursery places in Britain led to an enormous rise in the share of three-year-olds enrolled, from 37% to 88%. Yet only one in four of those enrolled would not otherwise have gone to pre-school. Although scores on assessment tests for this group rose substantially, they represented a small enough share of total participants that the average scores among all British children barely budged. Evaluations of universal pre-schooling in Quebec, where the government introduced highly subsidised early-childhood education for all in 1997, find that shifting children from private nurseries or lavish care at home into public facilities actually reduced children’s scores on measures of social development.

Those in favour of universality argue that it broadens political support for public pre-schooling. The benefits of early-childhood education take decades to materialise, after all, during which time backing for means-tested programmes might wane whereas support for universal pre-schooling would not. Supporters also reckon that mixing students of different backgrounds improves the experience of poorer children. Yet as with universal primary and secondary schools, richer parents will often opt out of the public system, or segregate themselves from poorer children by moving to expensive neighbourhoods. In strict economic terms, money focused on the disadvantaged is money better spent—provided society remains committed to the investment.

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