It’s a Boon to Politicians and Parents, But Does Universal Pre-K Really Help Kids?

A topic of fierce debate among researchers.

Illustration by the Heads of State.
Illustration by the Heads of State.

When they toddle into their pre-Kindergarten classrooms next week, New York’s 4-year-olds will embark on one of the city’s most ambitious social initiatives in decades. Some 53,000 kids, more than twice as many as last year, will attend full-day pre-K, en route to a universal cohort of 73,000 slated for the following school year. Public school districts and community not-for-profits are dry-walling classrooms and ramming new teachers through crash courses in early childhood development to accommodate them. Such was the rush that nearly 1,000 pre-K students are at least temporarily out of luck, after the city’s last-minute announcement that 45 programs were either not suitable for funding or simply not ready.

The frantic mobilization is the centerpiece of Mayor de Blasio’s vision for the city and carries with it an enormous weight of hope and ideology. Echoing the soaring language of great progressive causes, his campaign promised it would “promote equity and social and economic justice”—a populist message underscored by his proposed funding mechanism, a redistributive tax on the rich with incomes above $500,000.

Mayor Bill de Blasio, who crusaded for universal pre-K, visits P.S. 1 in Brooklyn.
Mayor Bill de Blasio, who crusaded for universal pre-K, visits P.S. 1 in Brooklyn.

That last part sounded a bit too Bolshevist in Albany, but pre-K fits equally well in wonkier packaging as a public investment that will pay for itself many times over in higher wages, lower crime and reduced welfare spending. President Obama’s proposals for universal pre-K stand little chance of getting past congressional Republicans, but at the state level universal pre-K’s broad appeal has made it one of the nation’s few bipartisan policy causes, enacted by politicians from blue New York to red Oklahoma, Georgia and Texas.

Universal pre-K is an idea whose time has come. With stay-at-home moms an endangered species, early childhood has become thoroughly institutionalized; society will therefore insist that it be edifying as well. And with education the only way anyone can think of to secure a foothold in an increasingly precarious economy that seems to reward only the most advanced skills and prestigious degrees, the public will increasingly demand that every scrap of education become an entitlement. But can universal pre-K shoulder the burden of expectations placed on it? Will it rejuvenate American education and propel kids to high-paying jobs? And can it really, as Mayor de Blasio suggests, even out the inequities that separate the haves from the have-nots?


To see the pre-K revolution in action I visited Fort George Community Enrichment Center, a Head Start center with a full-day program for 135 kids housed in a church in Washington Heights. With limited room in public schools, most of the 40,000 or so new full- and half-day pre-K slots will be filled by private and not-for-profit pre-schools like Fort George; Carolyn Wiggins, the executive director, says the center is ready to expand if space can be found. The 4-year-olds, about 20 per class with a teacher and an adult assistant, get a structured regimen of learning through play.

Tots sing along with a video character who waves his “one little finger” and then taps and names his leg, arm and chin, thus imparting number concepts and English vocabulary. A second group absorbs a multi-media primer on dental hygiene that flows from video to storybook and will end with the kids brushing. Rudimentary arithmetic problems and pattern recognition exercises are enacted with colored blocks. Furniture and toys are labeled in English and Spanish, and the kids’ drawings, replete with listing houses and Easter Island heads, are adorned with scrawled one-word captions, all to impart key “pre-literate” insight.

It’s an encouraging scene: the kids are engaged and attentive; the teachers, who must have bachelors’ degrees and be working towards teacher certification, are smart and skilled at the exhausting task of keeping 4-year-olds focused; the curriculum, which follows New York State’s Common Core standards, has constructive content.

And since Fort George’s students are from poor and mostly Spanish-speaking homes, pre-K will be especially helpful to them because of the opportunity to learn English and get used to a classroom setting before kindergarten. That should, in theory, initiate a virtuous circle in later grades: kids learn more in each grade because they enter better prepared, thus laying the groundwork for success in the next. “Skill begets skill; motivation begets motivation,” writes James Heckman, a Nobel Prize-winning economist at the University of Chicago and a leading pre-K theorist.

He models that dynamic as a stock of “human capital” whose returns compound dizzyingly over time; and like any compound-interest model, the earliest investments are the most lucrative. “The longer society waits to intervene in the life-cycle of a disadvantaged child,” Heckman writes, “the more costly it is to remediate the disadvantage.” The implication is clear: by kindergarten, it may be too late.

But how many returns do those investments really yield? As hopeful as the Fort George program is, there’s nothing magical about it. What kids get there in pre-K is what kids have gotten for decades in kindergarten, which is where I learned about counting and the alphabet and playing peaceably with classmates and sitting still during story time. And the weekdays kids spend at Fort George won’t erase the differences that yawn the rest of the time between them and the children of affluent households where bedtime reading and immersion in the King’s English and tooth-brushing and countless other enrichments are old hat long before they hit pre-school.

Given those persistent gaps in experience, can simply moving kindergarten up a year compensate for the additional troves of human capital lavished on well-off children, and meaningfully bridge the gap in school achievement?

Pre-kindergarten children at public charter school.


A major study of Head Start, the federally-funded pre-school program for poor kids, found that while Head Start kids registered clear gains in cognitive and academic skills by the end of the pre-K year, these had almost all faded out to statistical insignificance by the end of kindergarten.

It’s clear that pre-K does something for kids, but what it does—and how much, and for how long—is a topic of fierce academic controversy. Most of the education researchers I talked to support universal pre-K. Georgetown professor William Gormley called New York’s new universal pre-K program “a terrific idea” that could be “beneficial not only to the students but to society at large.” Mr. Gormley has studied Oklahoma’s universal pre-K program, which is often held up as a model, and found that at the start of kindergarten kids who got a year of state pre-K were nine months ahead in pre-reading skills, seven months ahead in pre-writing skills and five months ahead in pre-math skills compared with kids who didn’t. Pre-K attendance, he says, predicted verbal test scores better than race, family income or any other single demographic variable.

Rutgers economist W. Steven Barnett, director of the National Institute for Early Education Research, agrees. He points to the success of the Abbott program, a court-ordered universal pre-K program in 31 of New Jersey’s poorest school districts; his study of the program found significant gains in reading and math scores that persisted into the fifth grade, and a 30 to 50 percent reduction in the percentage of kids who had to repeat a grade.

But some experts are skeptical. Russ Whitehurst, director of the Brown Center on Education Policy at the Brookings Institution, criticizes the research supporting universal pre-K, and cites other studies that show a pronounced “fade-out” of positive effects as years pass.

A major study of Head Start, the federally-funded pre-school program for poor kids, found that while Head Start kids registered clear gains in cognitive and academic skills by the end of the pre-K year, these had almost all faded out to statistical insignificance by the end of kindergarten—and some measures of behavior and social adjustment showed a negative association with Head Start attendance.

A 2013 Vanderbilt University study of Tennessee’s state-run pre-K program found the same pattern: kids finished pre-K significantly ahead of their peers who didn’t attend in language, math skills and behavioral indicators, but by the end of kindergarten their cognitive advantages had dwindled away (although they were half as likely to repeat kindergarten). Long-term assessments of state pre-K programs in Georgia and Texas, Mr. Whitehurst notes, found effects on third- and fourth-grade test scores that were modest to nil. Mr. Whitehurst’s own work indicates a small association between a state’s pre-K attendance and an increase of a few points on fourth-grade reading and math scores. But he feels that universal programs waste money by funding pre-K for everyone instead of targeting resources on disadvantaged kids who need the most help—and may actually hurt middle-class and affluent kids by shifting them from enriched home care or high-end pre-K into mediocre state-run programs.


Public preschoolThe controversy over pre-K research is fueled by the fact that kids make lousy lab rats. Many scientists prefer “randomized control trials,” which take a group of pre-school applicants, enroll some and exclude others according to a flip of the coin, and assume the two groups are pretty much the same except for that random toss. Unfortunately, a rigorous randomized control trial is hard to do, especially for a universal state-run program that takes all comers.

The next best thing, according to proponents, is to leverage the fact that state programs use a birthday cut-off—say, before or after September 1—to decide whether kids get into that year’s pre-K class or have to wait a year. The random accident of birthdate creates two groups of kids who differ only a little by age: a “treatment” group that goes to pre-K and a slightly younger “control” group that stays home. Comparing their test scores after a year ostensibly lets you isolate the effects of a year of pre-K attendance on a youngster’s cognitive skills. These “regression-discontinuity” designs, like the Oklahoma and New Jersey studies above, tend to find the largest benefits from pre-K attendance.

But Mr. Whitehurst, who considers randomized control trials the gold standard, is wary of subtle disparities that he believes can throw off results. Treatment kids socialize with an older, savvier set than do the controls, he argues, and there’s a status gap that makes parents treat pre-Kers differently from younger stay-at-homes; both these effects can alter a child’s informal learning environment independently of the pre-school’s influence.

‘If you’re just running pre-K like you’re running a kindergarten and just adding another grade to the beginning, that really raises all the same issues you have with achievement gaps in K-12.’

There are also problems with the studies that show insignificant pre-K effects. The Head Start study was a randomized control trial, but it was compromised because some of the “treatment” kids didn’t end up attending Head Start, and many of the “control” kids who were supposed to be excluded went to Head Start anyway.

(Pre-K is now so widespread that it’s getting hard to find kids who don’t attend some kind of program to use as controls.) And the Tennessee study, Mr. Gormley and Mr. Barnett point out, was flawed because control kids had a much lower participation rate in the study’s tests than did treatment kids, a difference that may correlate with family differences that also skew their test results. Mr. Barnett reinterprets fade-out, which also emerged to some extent in follow-up studies on the New Jersey program, as “catch-up” by students who didn’t go to pre-school and got (expensive) remedial help in later grades.

All these nuances make the cognitive and academic benefits of pre-school look modest and muddled. In the esoterica of education research, those effects are often quantified as decimal fractions of a standard deviation, a measure of how far a particular student’s or group of students’ test scores deviate from the average of all student scores. A Washington State meta-analysis of 49 pre-K studies that Mr. Barnett sent me estimated that by high school, the improvements in test scores from having attended pre-K had dwindled to about 0.085 standard deviations, a fade-out of 73 percent. (To calibrate that, average test scores for black kids tend to differ from those of white kids by about 1.0 standard deviations.)

Mr. Barnett’s own Abbott study estimates the effects of a year of pre-K on fourth- and fifth-grade test scores to range from 0.12 to 0.18 standard deviations. When I asked him how much of an impact universal pre-K might have, Mr. Barnett guesstimated that we could expect it to close the achievement gap between disadvantaged and better-off kids by perhaps 10 percent—not an insignificant result, but maybe an underwhelming one given the messianic hopes for pre-K in some quarters.

Attention has therefore shifted from cognitive to social benefits: if pre-K doesn’t make kids much smarter, it may still improve other aspects of their ability to cope with life. On that score, two decades-long studies following pre-K alumni into adulthood register effects that are striking, if erratic. The Perry pre-school program, conducted in the mid-1960s with a group of disadvantaged African-American youngsters in Ypsilanti, Michigan, provided two years of intensive pre-K along with bi-weekly home visits. The immediate result was a spike in IQ scores that largely faded out. But there were longer-lasting benefits, including less grade repetition and a much higher high school graduation rate for girls. (Unfortunately, boys who went to pre-K were slightly less likely to graduate than those who did not.)

By age 40, the Perry alumni were more likely than controls to have jobs, had higher average earnings and were less likely to be involved in crime. (Although the headline there—36 percent of Perry-ites had been arrested five or more times, compared to 55 percent of controls—looks good only in relative terms.) The Abecedarian study of poor, mainly African-American kids in North Carolina found that attending pre-school improved school test scores in later grades, raised high school graduation rates, and boosted college graduation rates even more (23 percent vs. 6 percent for the control group). At age 30, the Abecedarians were much less likely to be unemployed or on welfare compared to controls, had better-paying and more prestigious jobs, and had a markedly stronger preference for tobacco over pot. (They were, however, just as likely to have criminal convictions.)

Another study by Harvard economist David Deming compared kids who attended Head Start to siblings who did not. The study found that, despite the usual fade-out of cognitive benefits, the Head Start grads had higher high school graduation and college attendance rates and lower rates of teen parenthood and “idleness”; crime rates, though, were unaffected. (Mr. Whitehurst criticizes this study, too, arguing that sibling differences might have arisen because parents preferentially pushed their brighter offspring into Head Start.)

Together these and other longitudinal studies paint a broad picture of modest cognitive gains but significant long-term benefits in educational credentialing, job success, health and good citizenship. Focusing on the latter, advocates often downplay academics and emphasize pre-K’s role in building “character,” as James Heckman puts it, by imparting “socioemotional skills”—self-control, cooperation, stick-to-it-iveness—that yield success at school and work.


These benefits are acknowledged by skeptics, but they also highlight the limits of pre-K as a social panacea. Perry and Abecedarian alumni are substantially better off than their peers on average, but as a group they are still crime-prone under-achievers by middle-class standards. And these programs are atypical models from which to project the potential of pre-K: small, specialized, lavish—the Abecedarian program admitted infants and nurtured them through third grade—and aimed at very poor kids for whom any enrichment was a godsend. It’s a stretch to extrapolate their results to large, bureaucratized, universal pre-K programs, which is why critics like Mr. Whitehurst prefer Perry-style programs that target a smaller group of at-risk kids rather than universal programs that spread limited budgets around.

Proponents ritually invoke the phrase “high-quality pre-K,” which implies that there is a lot of low-quality stuff out there. “It’s really important that this is an authentic educational experience and not a custodial experience,” says Mr. Gormley; and as access has grown more prevalent, quality has become the rallying cry for the pre-K movement. But the questions of what quality is, and how to get it, are knotty. Quality is assumed to correlate with institutional proxies: big budgets; small class size; teachers with BAs, early childhood certification and union-scale salaries. But ultimately it boils down to the imponderable relationship between teacher and child. “It’s getting inside each child’s head, to the point where you’re not teaching the classroom, you’re teaching 18 children,” says Mr. Barnett. “You’re asking, ‘What’s the next thing this child needs to learn to get along better with other kids? What’s the next thing that child needs to learn to crack the code on reading?’ ”

But it’s a safe bet that New York’s universal pre-K will be run very much like New York’s K-12 system, for which improving quality has proved an elusive and contentious goal. Tacking another grade on is something school bureaucracies know how to do, conjuring the perfect mind-meld of teacher and toddler not so much. “If you’re just running pre-K like you’re running a kindergarten and just adding another grade to the beginning, that really raises all the same issues you have with achievement gaps in K-12,” Mr. Deming says.

Indeed, to see the likely trajectory of pre-K we need only look at K. Fifty years ago, the movement for early childhood education centered on universal access to kindergarten, which was not a standard part of school then. The word “kindergarten” itself denotes the same utopian vision now swirling around pre-K: a model of learning through play and exploration at an age when young minds are at their most fertile, in a rich, cloistered environment that will erase external social disparities while preparing kids cognitively and behaviorally for the pressure-cooker of first grade. But as the kindergarten movement achieved the same goals now advanced for pre-K—universality and public funding; full-day attendance; the professionalization of the teaching staff—kindergarten itself became not the salvation of schools but merely an extension of them, Grade Zero of an educational system still widely perceived as inadequate and unfair.

Pre-K is now at the same point in its development—and ideology—that kindergarten occupied in the 1960s. Indeed, with over 60 percent of America’s 4-year-olds now attending some sort of program, the pre-K revolution has in large part already happened; whatever pre-K is going to do for kids it is mostly already doing. But as it marches towards ubiquity, it seems to bog down in all the problems that vex the larger school systems: doubts about quality and effectiveness, and controversies over how to improve them; yawning gaps between good and bad programs; dogfights over budgets, resources and governance. Whatever the benefits pre-K holds for kids, it will replicate rather than resolve the perennial discontents surrounding education. We will fret that pre-schools are leaving our kids unprepared for life and argue over which curriculum and discipline will whip them into shape. There will be good and bad pre-Ks, well-funded and ill-funded districts, threadbare pre-Ks for the poor and lavish private pre-Ks that simply add to the head start that rich kids are born with.


Pre-K won’t make kids equal; at best, it will help them adjust to an unequal world.

So pre-K will probably not be the great leveler of social inequities that Mayor de Blasio intends; like the larger universe of education, it will become one of the most glaring—and galling—indices of social inequity. Pre-K won’t make kids equal; at best, it will help them adjust to an unequal world.

That’s not nothing—for people born into poverty, better chances at stable jobs and stable lives are immensely important. But neither is pre-K an adequate response to the problem of unequal outcomes in adulthood. (Its greatest benefit in that regard may simply be to give parents free childcare, which is a heavy financial burden for middle- and working-class families.)

Worse, the implicit premise of pre-K—it’s all over by kindergarten—reflects a troubling philosophical concession to inequality. It acknowledges that formal education is not the great leveler that lets people of any age transcend their circumstances and chart their own course; instead, socioemotional propensities laid down before children are even conscious of them determine their chances in life.

Taken to its conclusion—if pre-K is good, aren’t pre-pre-K and pre-pre-pre-K better?—that logic begins to merge with an older, uglier belief that birth and breeding dictate our fate, that having gone to the wrong pre-school will limit a child’s prospects as surely as being born in the wrong family or the wrong skin once did (and may still).

When we’ve loaded toddlers up with all the human capital they can carry, when we’ve made Baby Einstein and Mozart in the womb entitlements, when there’s no more childhood left to enrich, then we’ll come full circle to a thornier problem: what to do with us grown-ups?  It’s a Boon to Politicians and Parents, But Does Universal Pre-K Really Help Kids?