Kindergarten Redshirting: Does Holding Kids Back a Year Pay Off?

At a preschool in suburban Chicago, a group of four-year-olds are in their last spring before kindergarten eligibility. Three of the boys in the room will be held back — their parents, almost all college-educated and upper-middle-income, have decided the boys aren’t “ready.” Their teachers, when asked privately, say all three are developmentally typical. What the parents have seen is the internet, other parents, and an increasingly competitive kindergarten landscape where being the oldest in the room feels like a competitive advantage. This decision — to delay a child’s kindergarten entry by one year — is called academic redshirting, and it is made for approximately 150,000 to 250,000 children per year in the United States. The research on whether it helps is more complicated than the people making the decision typically know.

Key Takeaways

• Approximately 5-8% of kindergarten-eligible children are redshirted annually in the U.S., with the rate significantly higher among white, affluent, and educated families.
• Boys are redshirted at roughly twice the rate of girls, and children with summer birthdays are the most common candidates.
• Research by Deming and Dynarski shows relative age effects — being the oldest in class — produce measurable early academic advantages that largely dissipate by third grade.
• Datar’s 2006 kindergarten study found short-term benefits for children who entered kindergarten later, but these benefits were concentrated in children who were developmentally delayed, not typical children.
• The economic cost of redshirting — one additional year of childcare or preschool, one less year of earnings over a career — can exceed $350,000 in lifetime impact.
• Children who are socially and emotionally ready but academically average tend to receive no meaningful long-term benefit from redshirting.

The Relative Age Effect: What Deming and Dynarski Found

The foundational research on redshirting’s mechanism is the work of Deming and Dynarski, published in a 2008 National Bureau of Economic Research working paper. Their analysis of large national datasets found a robust “relative age effect”: children who are the oldest in their kindergarten cohort — those born just after the enrollment cutoff — consistently outperform children who are the youngest in their cohort on early academic assessments.

This finding is real and has been replicated across multiple countries and educational systems. The oldest children in a kindergarten classroom have had 12 more months of brain development, language exposure, and motor skill refinement than the youngest. In a classroom where the youngest child is 4 years 8 months and the oldest is 5 years 8 months, those 12 months represent a developmental gap that is genuinely significant at that age.

What Deming and Dynarski also found — and what is frequently omitted in popular redshirting advice — is that this effect fades substantially by third grade and largely disappears by sixth grade. The academic advantage of being old for one’s grade is a kindergarten and early-elementary phenomenon. By the time students are 10-11, the 12-month age difference that dominated kindergarten outcomes has been swamped by actual learning, cognitive development, and accumulated educational experience.

The relative age effect also operates in both directions in ways that matter for the redshirting decision. If one family holds their child back, the children who do enter kindergarten that year now include more who are relatively younger. The intervention does not eliminate relative age disadvantage — it just changes who is disadvantaged. If redshirting becomes sufficiently widespread in a given cohort, the children who enter on time become the relatively younger group, and the redshirted children become the relatively older group. The relative effect is real, but it is zero-sum in a way that most redshirting advocates don’t acknowledge.

Datar’s Kindergarten Study: Who Actually Benefits

The most rigorous study of redshirting’s academic outcomes is Datar (2006), published in Economics of Education Review. Using Early Childhood Longitudinal Study data — a nationally representative sample of more than 20,000 kindergarteners — Datar examined whether children who entered kindergarten at older ages showed better academic outcomes, controlling for family background, preschool experience, and developmental status.

Her core finding was nuanced in a way that is critical to understand: children who entered kindergarten at an older age showed small but statistically significant gains in early reading and math — but these gains were concentrated almost entirely in children who had below-average school readiness scores when they entered. For children who were developmentally typical or above average on entry, the additional year of waiting produced no measurable academic benefit.

This finding reframes the redshirting question significantly. If your child is academically and developmentally ready for kindergarten by standard assessments, the research suggests that holding them back a year produces no discernible academic advantage. If your child is showing genuine developmental delays — in language, social-emotional regulation, or fine motor skills — waiting a year may help. The problem is that most redshirted children fall into the first category: they are typically developing children whose parents are worried about their readiness for competitive academic environments, not children with identified developmental delays.

Long-Term Academic and Social-Emotional Outcomes

The long-term evidence on redshirting is considerably less encouraging than the short-term data. Multiple studies examining outcomes at ages 10, 14, and into adulthood find that the early academic advantages of redshirting are either gone or reversed by late elementary school.

A 2015 study by Elder and Lubotsky, published in the Journal of Human Resources, followed a large cohort of redshirted and non-redshirted children through high school. Their findings showed that by high school, redshirted students had no significant academic advantage over students of similar ability who entered kindergarten on time. More troublingly, they found that redshirted students were slightly more likely to be referred for evaluation for learning disabilities in elementary school — potentially because teachers, unaware of a student’s redshirting history, flagged academic performance as below grade-level expectations that the student was not supposed to be meeting yet.

The social-emotional research is more mixed but also less favorable to redshirting than its advocates suggest. Some studies find modest social confidence advantages for older kindergarteners in the first year. Others find that by middle school, redshirted children are more likely to report social difficulties related to being the oldest in their peer group — a different kind of misfit than being the youngest. The research does not support the common parental assumption that an extra year of maturity produces lasting social-emotional advantages.

Outcome Domain	Short-Term (K-Grade 2)	Medium-Term (Grades 3-6)	Long-Term (High School+)
Reading achievement	Small advantage	Fades substantially	No significant difference
Math achievement	Small advantage	Fades substantially	No significant difference
Social confidence	Mixed; modest advantage	No consistent effect	No consistent effect
Behavioral problems	Slight reduction	Fades	No consistent effect
High school GPA	N/A	N/A	No advantage
College attendance	N/A	N/A	No advantage; slight penalty in some studies
Special ed referrals	Lower	Higher (misidentification risk)	N/A
Graduation timing	N/A	N/A	One year later by design

The Economic Argument Against Redshirting

The economic costs of redshirting are rarely part of the conversation, and they are substantial. The direct costs include an additional year of childcare or preschool — which averages $12,000-$20,000 per year in most U.S. markets and can exceed $30,000 in major cities. The indirect costs are larger and longer-lasting.

Deming and Dynarski’s analysis explicitly addresses the lifetime economic cost of delayed school entry. Their estimates, updated for contemporary wages, suggest that entering the workforce one year later — the inevitable consequence of starting kindergarten one year later — reduces lifetime earnings by approximately $50,000-$100,000 in present value, depending on the child’s eventual career trajectory. For high-earning professions, the gap is larger. This is not a parenting-advice consideration that shows up in most discussions of redshirting, but it is the economic context in which the decision is actually made.

Economists Cascio and Schanzenbach (2016), writing for the Brookings Institution, put the redshirting calculation bluntly: given that the academic benefits of redshirting largely disappear by middle school and that the economic costs compound over a career, the decision to redshirt a typically developing child is difficult to justify on a cost-benefit basis. Their analysis found that the children who show the most persistent redshirting benefits — those with developmental delays or genuine school readiness problems — are also the ones most likely to qualify for additional school-based support regardless of when they enter kindergarten.

For parents thinking about early childhood educational decisions and what actually predicts long-term success, the research on kindergarten readiness factors provides a more detailed breakdown of what assessments measure and what they actually predict. The question of when children are ready for structured academic work also connects to what the research shows about grade retention later in schooling — a decision with similarly mixed evidence despite widespread use.

Who Does and Doesn’t Benefit

The research converges on a fairly specific profile of the child for whom redshirting may provide meaningful benefit: a child who has an identified developmental delay (particularly in language development or self-regulation), who would be among the very youngest in their cohort (born within the last 4-6 weeks before the enrollment cutoff), and who attends a school with a highly structured, academically demanding kindergarten program rather than a play-based or developmental one.

Outside of this profile, the evidence for redshirting is weak. The typical redshirted child in the United States — a typically developing boy born in June or July whose parents are concerned about his readiness but who has no identified developmental concerns — is unlikely to see meaningful long-term academic benefit from the delay. The short-term advantages are real but temporary. The costs are real and permanent.

This matters because redshirting, as currently practiced, is heavily concentrated among high-income white families. Research by Bassok and Reardon (2013) in Educational Researcher found that redshirting rates among children from families in the top income quartile were more than twice those in the bottom quartile. The practice is not equally available: families who cannot afford an additional year of childcare cannot redshirt regardless of their beliefs about its benefits. The result is a policy that redistributes relative age advantage toward already-advantaged children, with no clear population-level benefit.

What to Watch for Over the Next 3 Months

If you are making a kindergarten entry decision for a child who will be eligible this coming fall, the next three months are the window for developmental screening if you haven’t already completed one. Pediatric developmental screenings — offered by your child’s pediatrician at the 4-year and 5-year well visits — assess language, motor skills, social-emotional development, and cognitive readiness. If a pediatric screening raises concerns, a referral to a developmental pediatrician or child psychologist can provide more detailed assessment.

The key question to answer before making a redshirting decision is whether your child has an identified developmental concern or whether your concern is primarily about competitive academic positioning. The research supports the former as a legitimate basis for delay. It does not support the latter.

Also watch for changes to kindergarten curriculum at your specific school. The character of kindergarten has shifted significantly in the last 20 years toward more academic content and earlier literacy expectations. In a play-based, developmentally oriented kindergarten program, the relative age effect is smaller — because the curriculum is designed for a range of developmental readiness. In a heavily academic program with early reading and writing requirements, the oldest children have more advantage. Understanding what kind of kindergarten your child will actually enter is relevant to the decision.

If you decide to wait a year, consider what that year will involve. A structured preschool environment that provides social learning, structured activity, and language-rich interaction produces better outcomes than a year of informal home care. The goal of the additional year, if you pursue it, should be developmental enrichment — not simply waiting.

Frequently Asked Questions

Is redshirting more common for boys than girls?

Yes, substantially. Boys are redshirted at approximately twice the rate of girls in the United States. The reason most cited by parents is that boys are “less mature” than girls at age 5 — a perception that has some basis in average developmental timing but significantly overstates the typical sex difference in kindergarten readiness. Research finds that the academic benefits of redshirting, to the extent they exist, are not meaningfully larger for boys than for girls of similar developmental status.

Does being the youngest in class actually hurt kids?

The relative age effect is real: the youngest children in a kindergarten cohort score lower on early academic assessments than the oldest children in the same cohort. However, this effect is a function of being young relative to classmates, not of anything inherent to the child. It fades as children age and largely disappears by middle school. Being the youngest in class does not doom a child; it creates a short-term academic environment where they are at a developmental disadvantage relative to older classmates.

What should a developmental screening include for a redshirting decision?

A kindergarten readiness screening should assess receptive and expressive language (can the child follow multi-step instructions and express ideas clearly?), self-regulation (can the child sit and attend to a structured task for 10-15 minutes?), fine motor skills (pencil grip, scissor use), and basic pre-academic skills (letter recognition, counting). These domains are more relevant to kindergarten readiness than intellectual ability. A child can be intellectually advanced and still have genuine readiness challenges in self-regulation or language — and those challenges, not IQ, are what kindergarten teachers are managing.

If we redshirt, does it help with sports recruiting later?

This is a widely cited reason for redshirting, particularly for boys in competitive youth sports. The research on athletic outcomes from academic redshirting is thin and largely unsupportive. Being a year older provides physical development advantages in youth sports, but by high school these differences are minimal. The NCAA has specific rules about academic eligibility that interact with grade-year calculations, and some families have faced complications when a student’s academic year and age don’t align with standard recruiting timelines.

Does redshirting affect a child’s social development?

The social research is mixed but generally does not support long-term social-emotional benefits from redshirting. Some studies find modest confidence advantages for older kindergarteners in their first year. By middle and high school, redshirted children sometimes report social awkwardness from being the oldest peer in a friend group, particularly around milestones like driving, dating, and graduating. There is no consistent evidence that redshirting produces lasting social-emotional advantages for typically developing children.

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About the author

Ricky Flores is the founder of HiWave Makers and an electrical engineer with 15+ years of experience building consumer technology at Apple, Samsung, and Texas Instruments. He writes about how kids learn to build, think, and create in a tech-saturated world. Read more at hiwavemakers.com.

Sources

1. Deming, D., & Dynarski, S. (2008). The lengthening of childhood. National Bureau of Economic Research Working Paper No. 14124. nber.org
2. Datar, A. (2006). Does delaying kindergarten entrance give children a head start? Economics of Education Review, 25(1), 43–62.
3. Elder, T. E., & Lubotsky, D. H. (2009). Kindergarten entrance age and children’s achievement. Journal of Human Resources, 44(3), 641–683.
4. Bassok, D., & Reardon, S. F. (2013). “Academic redshirting” in kindergarten. Educational Researcher, 42(2), 98–104.
5. Cascio, E. U., & Schanzenbach, D. W. (2016). First in the class? Age and the education production function. Brookings Institution.
6. Elder, T. E. (2010). The importance of relative standards in ADHD diagnoses. Journal of Health Economics, 29(5), 641–656.
7. Fortner, C. K., & Jenkins, J. M. (2017). Kindergarten redshirting: Motivations and spillovers using census-level data. Early Childhood Research Quarterly, 38, 44–54.
8. McEwan, P. J., & Shapiro, J. S. (2008). The benefits of delayed primary school enrollment. Journal of Human Resources, 43(1), 1–29.