Four-year-old Luke was starting kindergarten in Centerville, Ohio. He’d be one of the youngest in his class — turning 5 just before the school year begins — and his mother was concerned.

Historically, the starting age for kindergarten has varied widely. In recent years, both states and districts have pushed the minimum age to start kindergarten up so that more and more kids are at least 5 years old when they start school. (See minimum kindergarten entrance ages for all states as of 2018.) Still, in multiple states (Alaska, Indiana, Kansas, Minnesota, Missouri, Montana, Nevada, North Carolina, Wyoming) you can easily find a 5-year-old and a 7-year-old in the same kindergarten class, in Louisiana and Maine there might be a 4-year-old, and possibly 8-year-olds in Pennsylvania and Washington. That’s exactly what worried Luke’s mom, Deb Nelson, who has seen the difference just a few months can make, whether at home with her three sons ages 6, 4, and 3 or at school with the kids in her older son’s kindergarten class. Some kids are ready to read and write; others have trouble sitting still and paying attention. Being younger is particularly problematic as kindergarten becomes increasingly academic.

Delaying kindergarten is on the rise, both because state minimum ages are higher and because some parents are opting to wait until their children are older to start school. According to the most recent data available from the National Center for Education Statistics (NCES), in the 2019-2020 year the enrollment rate for 5-year-olds dropped 6 percentage points, to 84 percent. Will this benefit or hurt children in the long run? Educators are divided in their views. Rachel M. Robertson Ed.D. of Mississippi even claims in her 2021 paper “To Retain or Not Retain: A Review of Literature Related to Kindergarten Retention” that “it has been suggested that there is no other topic in education that has such a wide difference of opinion.”

Meanwhile, parents are wondering what to do, as they weigh the potential risks of starting kids in kindergarten when they’re either much younger or much older than other kids in their class.

Why redshirt?

Deb Nelson wasn’t only worried about kindergarten. “It’s junior high,” she says. “I don’t want him to be 11 when everyone else is turning 12 and have him be practically a year behind everybody in sixth or seventh grade.” Both concerns — for a child’s success in kindergarten and through adolescence — are driving forces behind the popular practice of “redshirting,” or delaying a child’s kindergarten entry by a year or more. (The term is borrowed from collegiate sports, where athletes will practice with the team for the first year, but sit out competition while they get bigger, stronger, and more competitive.)

Parents typically hold a child back because they feel he isn’t ready — cognitively, socially, or emotionally. Others may want to give their child a leg up, on the assumption that being older will make him more advanced. Who is the typical parent that chooses to delay kindergarten for their child? The answer is perhaps surprising.

Who redshirts their kindergartners?

NCES data for 2019-2020 indicates it is not high-income, super-educated white parents who seek the delay. Quite the opposite. Redshirting doesn’t “differ across racial/ethnic groups” but it occurs at a 9 percent higher rate if children have parents with only a high school degree, compared to families with college graduate Moms and Dads. More remarkably, redshirting is 22 percent higher in families with two unemployed parents, compared to families with both Moms and Dads employed.

Ten years ago, redshirting was more popular with more affluent families. It was the thing to do, says Gary Painter, a professor at University of Southern California’s Sol Price School of Public Policy, who authored a paper on redshirting. “Particularly in upper-middle-class circles where parents want to give their children every advantage, and want their kids to be ahead of their peers.” The NCES data at the time backed up Painter’s assertion. Of the roughly 6 percent of children clearly designated as “delayed-entry kindergartners” in 2012, parents tended to have at least a bachelor’s degree, and their family incomes tended to be well above the poverty line.

Does redshirting make a difference?

The benefits for redshirted kindergartners sometimes appear to be so small they might seem to be insignificant. A 2021 report, “Early School Outcomes for Children Who Delay Kindergarten Entry” by Jordan E. Greenburg and Adam Winsler of George Mason University, claims “[r]esults indicate that children who delay kindergarten entry slightly outperform their peers in the kindergarten year, but these differences disappear by the end of 1st grade.”

Another report, “Does the Age That Children Start Kindergarten Matter? Evidence of Long-Term Educational and Social Outcomes”, co-authored by Gary Painter of USC and Jane Arnold Lincove of University of Texas-Austin, is based on a longitudinal study that looked at academic and social outcomes of delayed kindergarten entry over the course of about 20 years. The researchers followed children starting at age 4 or 5 through age 25 or 26. Incredibly, they found no academic or social benefit to redshirting (The one exception? Varsity football.) In fact, they found a small benefit to being younger in terms of slightly higher college attendance rates.

Overall, research on has found mostly unfavorable results for being older than your grade-level peers, especially as a tween or teen. Robertson’s paper states, “…there is no reliable proof that grade retention is beneficial.” Research has also discovered unfavorable consequences for being among the oldest kids in class, including a study reporting an increase in social and behavioral problems in adolescence, when being older (or different in any way) can create problems. But that data is old (1998), and, in many cases, linked to studies on grade retention, which is likely more of a social stigma for a child than starting kindergarten later.

On the pro-redshirting side, a Canadian study suggests that redshirting can have positive academic outcomes, including a reduced chance that the child will repeat the third grade and improved math and reading scores in tenth grade.

Apparently, redshirting needs continued study, especially since the average age of kindergartners is on the rise. In the past 40 years, scores of states have raised their kindergarten cut-off dates. In 1975, only nine states required that kids be 5 when they start kindergarten. By 2018, all 50 states required children to be 5-years-old or almost 5 when they enter kindergarten. The most lenient state is Maine with the last-possible birthday on October 15.

Ready or not

In the meantime, it’s up to parents to determine their child’s kindergarten readiness on a case-by-case basis, taking into consideration social and emotional readiness, as well as cognitive ability. For many parents, evaluating a child’s kindergarten readiness isn’t easy. Former preschool teacher Tracy Gibb delayed her son’s kindergarten entrance because he was immature socially. “I’ve worked with kindergarten teachers for many years, and what they want are kids who can sit still and behave themselves well enough to learn, rather than a child who understands what’s going on but is a discipline problem because he’s too young to handle the responsibility of kindergarten,” she wrote in an email. Now, she thinks her 11-year-old son is on a par with his fifth grade peers emotionally. “This is a decision I have never regretted.”

When 4-year-old Delilah’s preschool teachers suggested she might not be ready for kindergarten, her mother, Los Angeles-based songwriter and music teacher Deborah Poppink Hirshland, was impressed with how the teachers explained their conclusion. In kindergarten, they told her, there are a lot of three-step processes, such as get a piece of paper, draw a shape on it, then cut out the shape. “Delilah went to the teacher after every step to ask what to do next,” Poppink Hirshland says. After an assessment, Poppink Hirshland learned valuable information about her bright daughter, who grew leaps and bounds thanks to occupational therapy. Later, 6-year-old Delilah thrived in kindergarten.

The school Nelson’s sons attend offers a young 5s program for kids who may not be kindergarten-ready. At a pre-enrollment panel discussion with four local kindergarten teachers, Nelson raised her hand and asked the all-consuming question: “When should my son start kindergarten?”

“One teacher said, ‘In my 35 years of teaching, I’ve never encountered anyone who wishes they hadn’t done the young 5s program, but I’ve encountered some who wish they had done it,'” Nelson recalls. She was sold, and asked to have Luke evaluated for the program. The assessment included tests of Luke’s fine- and gross-motor skills, attention span, attention to detail, ability to follow directions, number knowledge, ability to spell his name, alphabet knowledge, color vision, and a hearing test. Luke scored high and showed no discernable deficiencies. So despite actually being a young 5-year-old, he was deemed ineligible for the program.

Still worried her son wasn’t ready, Nelson went to the principal. “[The principal] said in his case, because he doesn’t have any deficiencies and scored so high, maybe a regular classroom would be better for Luke,” recalls Nelson. Still worried for her son down the road, Nelson made plans with the principal to have Luke take kindergarten twice. “We just tell him that he gets two years of kindergarten. He doesn’t have any feelings of being held back or retained.”

Yet another part of the equation with today’s high-stakes testing is that we expect more of kindergartners. Unfortunately, they’re less prepared for success. “Kindergarten is much more academic than ever,” says Emily Glickman, a Manhattan-based educational consultant. “Many people feel that kindergarten is the new first grade.” Reading expert and author of Raising Confident Readers: How to Teach Your Child to Read and Write — From Baby to Age Seven, J. Richard Gentry, PhD says the problem is exacerbated by parents failing to prepare their children for reading. Nearly half our nation’s kindergartners aren’t set up for reading success, he says. “The big question is whether a child is ready for formal reading instruction,” says Gentry, who explains that in terms of brain development, kids aren’t ready to read until age 6. But starting from birth, parents need to start preparing their kids to read with “joyful literacy activities” such as reading aloud, drawing, and playing writing games. According to Gentry, too many children aren’t getting this kind of preparation. “About 1.5 million kids come to kindergarten and they can’t write their name or retell the story of a favorite book,” he says. “They’re already behind. They’re the achievement gap.”

Who gets helped — and who gets hurt

Simply staying home and being a year older in kindergarten isn’t the answer. “We need to consider what the child is doing, when otherwise he would’ve been in an educational and enriching environment,” says Shane Jimerson, professor of school psychology at University of California at Santa Barbara.

Educational researcher Melodye Bush agrees. “It’s not good to start everyone later,” she says. “It’s not good to have everyone start at age 6. What we see is that the earlier you start [kids] learning to read and write, the better. As far as ability to retain knowledge, it’s better to start them at age 3.” Bush speculates that with time-strapped, stressed parents, “kids aren’t getting the necessary pre-learning they need.”

Both Gentry and Painter say that ultimately redshirted children from engaged, middle-class families “won’t be helped, but it likely won’t hurt.” But the practice puts a strain on families that don’t have the resources to pay for an extra year of preschool. If these younger kids have to compete with older, better-prepared children, it will, “exacerbate the achievement gap that already exists,” Painter says. “I don’t advocate that school districts ban redshirting, but it’s a caution to keep in mind.”