As states pass laws requiring schools to follow the “science of reading,” one aspect of these policies has stirred up particular controversy: Holding back struggling readers who don’t reach proficiency by the end of 3rd grade.
Some research shows that states with these retention policies have seen bigger student test-score increases than states without them.
Now, a new study suggests that the benefit to kids doesn’t actually come from having them repeat a grade. Instead, it stems from the extra reading support that’s unlocked when students are flagged for retention.
Researchers at the University of Michigan and the University of Pennsylvania analyzed reading scores for more than 168,000 students who were 3rd graders in Michigan during the 2020-21 and 2021-22 school years, when the state had a retention policy in place. (Gov. Gretchen Whitmer, a Democrat, signed a bill to repeal the policy in 2023.) They compared students who scored just below the cutoff for retention on the state test to students who scored just above.
Third graders who scored just below the cutoff received access to reading support services, which varied by district—offerings like summer reading programs or high-dosage tutoring. This group of children scored 0.045 standard deviations higher than the group of 3rd graders who scored just above the cutoff, and didn’t receive these services.
Districts saw these effects even if they didn’t actually hold back any students.
“It’s not a really big effect, but it’s something that is meaningful to consider,” said Brian Jacob, a professor of education policy at the University of Michigan, and an author on the paper. The difference amounts to about an eighth of the growth that students would typically make between 3rd and 4th grade, he said.
While the study implies that retention itself isn’t doing much to move the needle on students’ reading outcomes, it doesn’t necessarily mean states should get rid of retention requirements altogether, Jacob said.
Perhaps the high stakes of retention act as a catalyst for districts to zero in on student performance and prioritize extra services.
“If there weren’t this potential for mandated retention,” he asked, “would states and districts have the political will to provide the supports in the first place?
Can the ‘threat’ of retention ensure students get the support they need?
At least 26 states and the District of Columbia tell school districts to hold back 3rd graders who don’t reach reading proficiency by the end of the year, though most offer exemptions, according to a tracker maintained by the Education Commission of the States.
Third grade is regarded as a turning point in reading, when students are expected to read more complex text across the school day. If they can’t read at grade level in upper elementary school and beyond, it’s much harder for them to learn new material in any subject, from social studies to science to math.
But whether giving kids another shot at mastering reading skills in a second 3rd grade year actually leads to better outcomes is an open question.
Studies out of several states—including Florida, Indiana, and Mississippi—have shown that retention in early grades leads to higher student test scores down the line. Other analyses have underscored a key component of these policies. Retention schemes that offer additional academic support to students, beyond just repeating the same academic content, are more likely to lead to positive outcomes, those analyses have found.
Still, some research has shown negative social-emotional outcomes for retained students. And retention policies disproportionately affect students of color and students from low-income families.
Further complicating the literature is the fact that, in many states, few students are actually retained. That was the case in Michigan, where the new study took place. About 5.8% of 3rd graders who took the state test were eligible for retention during the 2021-22 school year, but only 0.6% of students were held back, according to a report from researchers at Michigan State University’s Education Policy Innovation Collaborative.
But this is a feature—not a bug—of a strong system of statewide reading supports, said Kymyona Burk, a senior policy fellow at ExcelinEd, an education advocacy organization launched by former Florida Gov. Jeb Bush. The group has written model legislation for early reading instruction that includes 3rd grade retention.

“Retention is not the goal of the retention policy,” Burk said. “The goal is for students to be identified early and receive the tutoring, the attention, the individualized reading plan to prevent a student from being retained.”
Retention policies are effective because they motivate adult behavior, Burk said.
It’s possible that’s what happened in Michigan, said Jacob. As part of the state’s Read by Grade 3 law, teachers in grades K-3 were required to give periodic reading assessments and provide extra support to those students who were struggling in advance of the 3rd grade assessment.
“There, I think maybe the threat of retention really could have influenced the effectiveness of those services,” he said.
States should be collecting data on the effect of support services, researcher says
Of course, retention wasn’t a totally empty threat in Michigan—more than 500 students were held back in 3rd grade in the 2021-22 school year, for example.
The policy had unequal effects. Students from low-income families who scored below the cut-off on the state test were more likely to be held back than students from high-income families who scored similarly.
Researchers who studied this phenomenon suggested that the difference might stem from parent advocacy. Students can avoid retention by employing one of several “good cause” exemptions, which higher-income families might have had more success pursuing, they hypothesized.
In 2023, when the state Senate advanced the bill that would eliminate Michigan’s retention requirement, Democratic state Sen. Dayna Polehanki said that the change would “ensure our kids have the reading supports they need—and eliminate the punitive and problematic mandatory retention piece they don’t.”
Several states require that districts create individual reading plans for struggling students and provide evidence-based interventions, without also requiring retention. But it’s hard to know whether they are moving the needle on student learning because most states’ longitudinal data don’t track the specific interventions students receive, Jacob said.
“Usually that’s held at the school or district level, so it makes it hard for researchers to dig in,” Jacob said. “If early literacy is really a priority, and states want to focus on this, and they think the support services are a key component of this, they should be collecting data and looking at the data.”