When my son was about to turn 5, I was faced with a decision that may be familiar to parents of children whose birthdays are close to kindergarten registration deadlines.
In my local school district, children must be 5 years old by September 1 before enrolling in kindergarten. With a late September birthday, my son was only a few weeks too young to reach that threshold. A friend of mine whose child had a birthday at the same time was trying to register early. Should I too?
In the end, I decided against it, sinking thousands of dollars for another year of preschool schooling. Instead of starting kindergarten a few weeks before he turned 5, my son started when he was just a few weeks away from turning 6. And while I wasn’t “redshirting”—intentionally holding my child back for a year when he otherwise would have been allowed to enroll—the supposed benefits of redshirting were part of my thinking. Of course, I thought, boys need more time to mature, and starting school with the oldest group in his cohort would be a clear victory.
But are these perceived benefits of redshirting – a term borrowed from athletics and sports eligibility rules – really true? A new study suggests that the academic improvement children may experience when they are the oldest in their kindergarten class fades by the time they reach third grade.
“For the average child, they’re not going to get a big advantage,” said Megan Kuhfeld, director of growth modeling and data analysis at NWEA, an assessment and research organization behind Measures of Academic Progress, or MAP, tests used by tens of thousands of schools across the country.
For this analysis, NWEA studied the 3 million students who attended kindergarten through the second-grade MAP Growth assessment between 2017 and 2025. Researchers also followed a cohort of students who started kindergarten in the 2021-22 school year to see what their test scores looked like when they were in third grade, compared to when they entered school.
Students who started kindergarten a year later than their peers had measurable advantages in reading and math. Compared to the average academic growth of kindergartners, the academic advantage of “redshirt” children represented 20 to 30 percent of a school year of learning.
This advantage did not last long, however. By the time students entered third grade, children who had been held back for a year no longer stood out from their peers academically.
The NWEA study didn’t delve into the factors behind these results, but Kuhfeld has a few theories. First, it might benefit children to have older peers in the classroom who serve as academic and behavioral role models. In other words, children like my son, who started school at age 5, could have a positive influence on children who turned 5 shortly before the kindergarten application deadline. Children who are already much older than their grade level peers have no role models to imitate.
The benefits of starting school later could also disappear, as children who enter school already familiar with the kindergarten curriculum may become bored, Kuhfeld said. Classrooms are not necessarily designed to push children who already meet academic standards; instead, the teacher is likely to focus on the children who need more help.
One of the most surprising findings of the study to me was that the wearing of red shirts is relatively rare. For each of the grades studied, about 5 percent of kindergartners started school a year after they were officially eligible. This figure peaked at 6.4% in fall 2021. The children most likely to be held back for a year are white college students and boys; redshirts were also more common in rural and low-poverty schools.
Given the rarity of the phenomenon, we certainly talk about it a lot. Kuhfeld said this could be because people are more aware and concerned about the higher academic demands of kindergarten. Additionally, Kuhfeld said, the idea of restraining children gained more attention after a prominent author, Richard Reeves, wrote a paper in 2022. recommending that all boys wear a red shirt to give them an extra year for their brains to mature. (Rise Together, a fund created by Reeves, is one of several donors to the Hechinger report.)
Kuhfeld said the study focused only on academics, not behavioral outcomes or other factors, so parents should make decisions that work for their individual children.
But there are social implications to being older than peers at the same grade level, she noted. Parents of kindergartners may not think about it when their kids are young, but what does it mean to be the first of your friends to hit puberty, or one of the oldest high schoolers? “It’s worth considering that there are tradeoffs,” Kuhfeld said. “It’s often described in conversations as, ‘Of course you would do that,'” she added. “There’s actually a lot of nuance here.”
This story about kindergarten redshirts was produced by The Hechinger Report, an independent, nonprofit news organization focused on inequality and innovation in education. Subscribe to the Hechinger newsletter.
The article Delaying Kindergarten May Have Limited Benefits appeared first on The Hechinger Report.
