The question often arrives in May or June, when summer feels close and the fall feels impossibly far away. Your child turns five in July or August. The cutoff for kindergarten in your district is September 1. Technically, your child is eligible. But should they go? A preschool teacher mentions, almost casually, that some parents in your situation choose to wait a year. A neighbor whose son has an August birthday decided to hold him back—and he thrived. Another parent at the playground says her daughter, also a summer baby, started on time and struggled socially for years.

And so the worry begins. You find yourself watching your child at the playground, trying to assess their maturity through a new lens. Are they ready? Would an extra year at home—or in preschool—give them some kind of edge? The term for this practice is "academic redshirting," borrowed from college athletics, where coaches sometimes hold freshmen out of competition for a year to let them develop. The thinking is similar: give children the gift of time, and they'll enter kindergarten older, bigger, more emotionally equipped to handle the demands of school.

The instinct behind redshirting makes intuitive sense. A year is an enormous span in the life of a five-year-old. The difference between a child who just turned five and one who's nearly six can be striking—in vocabulary, in impulse control, in the ability to sit still and focus. Malcolm Gladwell popularized the idea in his 2008 book "Outliers," pointing out that many elite hockey players are born in the first months of the year, giving them a relative-age advantage that compounds over time. Parents who can afford to give their children that advantage often feel they should.

But here's the thing: the research on kindergarten redshirting tells a more complicated story than the playground wisdom suggests. And for many families, the decision involves trade-offs that rarely get discussed.

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Let's start with what researchers have actually found. Studies consistently show that redshirted children do, in fact, perform somewhat better than their younger classmates in the early grades. A 2024 study published in the Journal of Research on Educational Effectiveness examined what happened when North Carolina shifted its kindergarten cutoff date, forcing some children to delay entry. The researchers found that these "forced" redshirts showed modest gains in math and reading achievement in third through fifth grade, and were less likely to be identified as having a disability.

But here's the crucial caveat: those advantages tend to fade. Research from Stanford's Center for Education Policy Analysis and elsewhere suggests that by second or third grade, the academic edge of being older largely disappears. A 2006 study that followed children into adulthood found even more sobering results: redshirted kids performed worse on tenth-grade tests, were twice as likely to drop out of high school, and were less likely to graduate from college. The only lasting advantage? They were marginally more likely to play varsity sports.

"A balanced look at the research suggests that while children derive a short-term gain from being redshirted, that advantage dissipates quickly over time," notes an analysis published by the Ohio State University Extension program. The gains parents hope for—that early boost translating into lasting academic success—don't appear to materialize in the ways they expect.

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One finding that genuinely should give parents pause involves ADHD. A widely publicized 2018 study published in the New England Journal of Medicine by researchers at Harvard Medical School examined the records of more than 407,000 children and found something striking: in states with a September 1 kindergarten cutoff, children born in August were 30 percent more likely to receive an ADHD diagnosis than children born just a month later, in September. The August-born children were the youngest in their classes; the September-born were among the oldest.

"Our findings suggest the possibility that large numbers of kids are being overdiagnosed and overtreated for ADHD because they happen to be relatively immature compared to their older classmates in the early years of elementary school," said Timothy Layton, the study's lead author. The difference between a six-year-old and a nearly-seven-year-old can be enormous in terms of the ability to sit still and focus—but teachers evaluating classroom behavior may not always account for that developmental gap.

A related study from Michigan State University estimated that nearly one million children may be misdiagnosed with ADHD simply because they are the youngest and least mature in their kindergarten classes. For parents worried about their summer-born child being pathologized for developmentally normal behavior, this research offers real cause for concern. Being the youngest in the room does seem to carry real risks of being judged against an unfair standard.

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What about the social and emotional benefits that parents often cite as their primary motivation for holding a child back? Here, too, the evidence is less encouraging than many expect. A 1997 study found that adolescents whose school entry had been delayed actually exhibited more behavioral problems than their classmates. Some research suggests that redshirted students may have poorer social-emotional outcomes, not better ones. The assumption that an extra year automatically produces greater emotional maturity doesn't hold up under scrutiny.

Thomas Dee, a professor at Stanford Graduate School of Education who directs the university's Center for Education Policy Analysis, has noted that researchers may have been looking in the wrong places when evaluating redshirting. "We reflexively look at test scores and educational attainment," he observed. "But if you start to unpack how developmental psychologists think about the gains of delaying school, it's really about other measures." Yet even when researchers examine those other measures—self-regulation, focus, behavior—the evidence for redshirting's benefits remains mixed at best.

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There's another dimension to this conversation that often goes unmentioned when parents discuss redshirting at preschool pickup: equity. Research from Stanford and the University of Virginia has consistently found that redshirting is overwhelmingly a practice of white, higher-income families. About 6 percent of white children nationwide are redshirted, compared with just 1 percent of Black children. Children from higher-income families are redshirted at twice the rate of children from lower-income families.

The reason is straightforward: redshirting requires resources. Public kindergarten is free. An additional year of preschool or childcare is not. For families living paycheck to paycheck, keeping a child out of free public school for another year simply isn't an option. As Daphna Bassok, a researcher at the University of Virginia who has studied redshirting patterns, puts it: "Redshirting is far too expensive for less-affluent families."

This creates what some researchers have described as an "arms race" dynamic. In affluent communities and private schools, redshirting becomes normalized—expected, even. The classroom fills with older children, making the younger ones seem even more immature by comparison. Parents who might otherwise have sent their summer-born children on time feel pressure to hold them back too, lest their child be at a disadvantage. Meanwhile, lower-income families who cannot afford to participate in this arms race see their children competing against classmates who are sometimes a full year older.

Richard Reeves, a senior fellow at the Brookings Institution who has written extensively about education and inequality, has noted the irony here: research suggests that delayed entry may actually be more beneficial for children from less advantaged backgrounds. But those are precisely the families who cannot afford to make that choice. Some school districts, including New York City's, have responded by forbidding redshirting on equity grounds. Parents with means, of course, can always opt out of the public system entirely.

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Perhaps the most important caveat in all of this research involves children with disabilities or developmental delays—or children whose parents suspect they might need extra support. For these families, the calculus shifts dramatically, and in a direction that may surprise parents whose instinct is to give their child "more time to mature."

Public schools are required by federal law to provide services like speech therapy, occupational therapy, and learning support to children with identified needs—at no cost to families. These services are often more effective when provided early. Research consistently shows that early intervention before age five produces better long-term outcomes than intervention that begins later. The Centers for Disease Control and Prevention notes that "intervention is likely to be more effective when it is provided earlier in life rather than later."

A 2016 study published in Early Childhood Research Quarterly compared outcomes for redshirted children with and without disabilities. The findings were striking: while children without disabilities who were redshirted showed modest gains in math and reading by third grade, children with disabilities who were redshirted actually scored significantly lower in mathematics than similar children who had started school on time. For these children, delaying kindergarten didn't provide an advantage—it delayed access to services they needed.

If you suspect your child may have a speech delay, a learning difference, or any other developmental concern, the research is clear: starting school on time—and accessing the free services available through the public school system—is likely a better choice than waiting. The extra year at home or in preschool won't provide the specialized support your child needs, and the delay in receiving that support may make it harder to catch up later.

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So where does this leave parents facing the decision? The honest answer is that there is no universally right choice. The research does not support the popular belief that redshirting provides lasting academic or social advantages for most children. But neither does it suggest that starting a young child on time is guaranteed to cause problems. The ADHD misdiagnosis research is worth taking seriously—but it's also worth noting that this is a risk, not a certainty, and that thoughtful teachers and pediatricians can account for developmental differences.

What matters most, ultimately, is your individual child—not the child next door, not the statistics in a research study. Some children genuinely thrive with an extra year of play-based learning before entering formal schooling. Others are eager and ready at five. A child who tends to compare themselves to peers and gets upset when falling behind might do better as one of the older students. A child who gravitates toward older role models might benefit from starting on time.

If you're weighing this decision, it may help to focus less on competitive advantage—the data suggests that's largely illusory anyway—and more on what your child actually needs right now. Consider their self-regulation skills, their stamina for a full school day, their ability to navigate social situations. Talk to their preschool teachers. And if you have any concerns about developmental delays or learning differences, remember that starting school opens doors to free, evidence-based services that could make a real difference in your child's life.

The gift of time is a lovely idea. But time, it turns out, is not the only gift parents can give. Sometimes the greatest gift is access—to teachers who will meet your child where they are, to services that can help them grow, to a classroom community where they can learn not just academics but the harder lessons of patience, perseverance, and getting back up when they fall behind. Those lessons, research suggests, may matter more in the long run than whether your child enters kindergarten at five or at six.

Sources

  • Bassok, D., & Reardon, S.F. "Academic Redshirting in Kindergarten: Prevalence, Patterns, and Implications." Stanford Center for Education Policy Analysis, 2013.
  • Layton, T.J., et al. "Attention Deficit–Hyperactivity Disorder and Month of School Enrollment." New England Journal of Medicine, November 2018.
  • Cook, P.J. "Redshirting Boys and Academic Achievement." National Bureau of Economic Research Working Paper, 2018.
  • Bassok, D. "The Truth About Redshirting." University of Virginia Magazine, 2013.
  • Fortner, C.K., & Jenkins, J.M. "Kindergarten Redshirting: Motivations and Spillovers Using Census-Level Data." Early Childhood Research Quarterly, 2017.
  • Reeves, R. "Who Redshirts?" Brookings Institution, September 2022.
  • Reeves, R. "How Much Does It Benefit a Child to Delay Kindergarten Entry for a Year?" Brookings Institution, December 2016.
  • Dee, T. "Hold Them Back? Stanford Education Professor Explains the Research on Kindergarten Redshirting." Stanford Graduate School of Education, 2023.
  • Elder, T. "The Importance of Relative Standards in ADHD Diagnoses: Evidence Based on Exact Birth Dates." Journal of Health Economics, 2010.
  • Brown, C. "How Kindergarten Redshirting Is Changing." Education Week, October 2024.
  • Centers for Disease Control and Prevention. "Why Act Early if You're Concerned about Development?" 2024.
  • Range, B., et al. "The Effects of Academic Redshirting and Relative Age on Student Achievement." ERIC, 2011.
  • Jones, S. "Academic Red-shirting: Perceived Life Satisfaction of Adolescent Males." ProQuest Digital Dissertations, 2012.
  • Dougan, K. "Forced to Redshirt: Quasi-Experimental Impacts of Delayed Kindergarten Entry." Journal of Research on Educational Effectiveness, 2024.