Congress is considering universal pre-K and subsidies for child care. Research shows how these policies can benefit children, and when they can backfire.

Congress is nearing a vote on a plan to spend around $390 billion over six years on early childhood care and education in the United States. Government-supported child care can have lifelong benefits for young children and their families, but it depends how the policies are designed.

The proposal, part of the safety net spending bill, would make financial assistance for child care near-universal, and pre-K for all children ages 3 and 4 free. Democrats hope it is popular enough to be extended after six years.

Similar ideas have been tried in cities like Boston and New York City, and states like Oklahoma and Georgia. Most rich countries spend significantly more than the United States on helping families with child care, and it’s common for the option of public school to begin at age 3.

Research on these programs offers evidence about what works and what doesn’t.

How, and whom, it helps

The bulk of the research shows that high-quality preschool tends to benefit children into adulthood, especially children from low-income families.

In school, gains in achievement test scores don’t generally last past early elementary school, but other measures, like graduating from high school and not repeating grades, do. Most studies suggest a benefit in social-emotional skills — pre-K graduates show better self-control and are less likely to be suspended or arrested. They are also more likely to have health problems diagnosed early. 

The effects are larger for children whose parents are poor; Black or Hispanic; or did not finish high school. Rich, highly educated families have more resources to provide high-quality options, at home or in private preschools — researchers say this is why some studies have found that children from high-income families do worse after public pre-K than their peers who don’t attend. The effects are also larger for boys. Other research shows that boys are more sensitive to both disadvantage and interventions.

The evidence is less clear-cut on child care for infants and toddlers. While some studies show the youngest children can thrive in high-quality programs, others suggest that attending center-based care before age 2 is associated with worse social skills or other behavior problems.

Child development is one of two aims of these policies. The other is enabling mothers to work. On that measure, child care subsidies clearly help, research shows. This may be the driver behind another benefit found in multiple studies: When children attend publicly funded programs, their parents tend to spend more time reading to them and showing affection at home.

Quality matters most

The clearest finding from the research is that the benefits come only when programs have high quality. Otherwise, they can do more harm than good.

A study on the effects of welfare reform found that work requirements without support for high-quality child care led to “intense exposure to low-quality care,” and that this had negative effects on children’s reading, math skills and behavior.

Quebec’s two-decade-old public child care has had uneven quality, with some studies finding emotional problems, physical aggression and decreased social skills for certain children. This was probably because alternatives like parental care or private child care centers were of higher quality, economists analyzing the data found.

Things that contribute to quality are a research-based curriculum; stimulating spaces and materials; education and coaching for teachers; and small group sizes. But the biggest piece, researchers said, is how the teachers interact with children — whether they are on the floor playing with them, using rich language, teaching problem-solving techniques and providing emotional support.

“The quality literature is pretty clear that credentials matter, yes, but what really matters is these moment-to-moment interactions,” said Bruce Fuller, a sociologist at the University of California at Berkeley Graduate School of Education.

The bill in Congress includes quality thresholds. It says that within six years, all children should be able to secure a spot in a center of the highest quality. It also has grants that include teacher training and building improvements. Still, requiring quality doesn’t guarantee it. Studies of New York City’s public pre-K have found that quality is uneven, and that mostly white and Asian preschools had larger increases in quality than those in Black and poor areas. Achieving high quality nationwide, across new and existing preschools in such a short time, would be a much bigger challenge.

Quality starts with teachers’ pay

The No. 1 way to improve quality, researchers say, is to pay teachers more. Child care is one of the worst-paid professions in the country. The median wage for a child care worker is $12; for a preschool teacher, it’s $15. In Virginia, simply paying teachers a $1,500 bonus if they stayed for eight months decreased turnover by half.

“We have decades of research on what high quality means when we think about kids and learning, and it always comes down to the teachers,” said Daphna Bassok, an associate professor of education and public policy at the University of Virginia who studied the state’s teacher retention program. “When you have a little extra money to get through life crises that hit hard when you live in poverty, you’re able to stay in your job, and we know that for little kids, keeping your teacher consistent, building warmth and connection, is the baseline level of quality.”