This story about working moms was produced by The Hechinger Report, a nonprofit, independent news organization focused on inequality and innovation in education.

WASHINGTON, D.C. — Ameykay Stocks, a mail carrier and a mother of five, has sent all her children to local public schools here from the year they turned 3.

She and her husband, a sign installer, have been grateful to have free child care while they worked. And she said she’s thrilled with what her children, now ages 5 to 16, have learned.

“She’s mastered puzzles on her own,” Stocks said of her 5-year-old. “She’s not into electronics, more into the whole fantasy land of kitchen and playing with pots and pans.” In her daughter’s preschool classroom last year, “she had a whole pet center and was playing chef and taking orders.”

Stocks expects all five of her children to complete college, something she never achieved, and credits some of their academic success to having a highly qualified classroom teacher since the age of 3.

Most families in America lack such an option. Nationally, only 68 percent of 4-year-olds and 40 percent of 3-year-olds were enrolled in preschool in 2017, according to the National Center for Education Statistics. Hardly any children younger than 3 are enrolled in publicly funded child care of any kind.

But Washington is one of a growing number of cities to offer public preschool, and it’s more generous than most: All 4-year-olds and most 3-year-olds living here, regardless of their family’s income, get a spot in a free public preschool program. A handful of other cities, along with a few states, such as Oklahoma and West Virginia, offer free preschool as well, making public education available to children younger than 5.

Two students answer their teachers' questions about apples during their preschool class at Kimball Elementary School in Washington, D.C. Lillian Mongeau / The Hechinger Report

Led by Sen. Elizabeth Warren, D-Mass., some of the Democratic presidential candidates have set their sights on an ambitious — and costly — national child care system that would constitute a vast expansion of these local programs. In early 2019, Warren proposed a policy that would provide working families with free child care. This month, Sen. Bernie Sanders, I-Vt., followed suit, releasing his own universal child care plan. Warren, Sanders and Sen. Amy Klobuchar, D-Minn., all mentioned the importance of expanding child care during Tuesday’s South Carolina debate.

“Instead of giving tax breaks to billionaires,” Sanders said, “we're going to have high-quality, universal child care for every family in this country.”

Such a change would affect millions of families. Across the country, two-thirds of women with children younger than 6 work. This means a lot of kids — 21.3 million of them, according to the National Center for Education Statistics — are cared for regularly by someone other than their mother.

Related: How cities are convincing voters to pay higher taxes for public preschool

Despite these overwhelming numbers, the federal government does little to subsidize child care. That hurts working moms, who are more likely than working dads to quit their jobs when they can’t find child care, according to a survey conducted by the liberal Center for American Progress think tank. And working moms were 40 percent more likely than working dads to say that child care issues had negatively affected their careers.

“We don’t have the supports that women need to stay in the workforce consistently if they want to,” said Julie Vogtman, the director of job quality at the National Women’s Law Center. “If women work, it’s difficult to earn enough to afford child care. But if they take time out of the workforce, both their family’s short- and long-term financial stability are harmed by that choice.”

‘It relieved a lot of stress’

For Stocks, Washington’s public preschool program has meant that she could keep the jobs she needed to make ends meet for her family and also have the time to earn the certifications she needed to improve her work prospects.

When her oldest child, Justina, was born, Stocks was working at Macy’s and Kay Jewelers and was having trouble affording the $68 a week she owed for child care after receiving city subsidies for low-income families. Stocks needed multiple forms of public transportation to get to the child care facility, then to her two jobs and then back in time to get Justina. Some days, she’d end up spending $20 she could ill afford on a taxi to get back in time.

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Things became easier when Justina turned 3 and became eligible for the preschool program at her neighborhood school: Garfield Elementary. The school was easier to reach, the cost of child care dropped (Justina still went at 6 a.m. before school started at 8 a.m.) and Stocks was happier with the quality of care.

“It relieved a lot of stress off of me,” she said.

Since then, Stocks earned a certification at University of the District of Columbia Community College that allowed her to qualify for a job at the U.S. Postal Service where she’s able to earn a higher and steadier salary. She said without free, full-time child care, she couldn’t have made that switch.

Related: Finding a good preschool isn’t easy: Try it.

Washington’s publicly funded full-day preschool program was responsible for increasing the city’s maternal labor force by 10 percentage points from 2008 to 2017, according to research published in 2018 by the Center for American Progress. Researchers determined that the bump in employment affected women at both the upper and the lower ends of the pay scale. Those in the middle, already a highly employed group, did not see much change.

Teacher Irene Taguian leads a 4-year-old preschool class at Lafayette Elementary School in Washington, D.C. Lillian Mongeau / The Hechinger Report

Nationally, the American female workforce is shrinking and the birth rate is slowing, neither of which are good for the country’s bottom line. Just 57 percent of women work now, compared to a high of 60 percent in 1990, according to the U.S. Bureau of Labor Statistics. Women have been having fewer children year over year for about the same amount of time, even though many report wanting more than they have.

Mary Charles and her husband, who have one child, live in Washington. She is an information technology manager at a government office and he is a government contractor. They are firmly middle-income earners in their city and say paying for child care in the years before their daughter could start preschool was a big stretch.

“It was $20,000 a year and that’s considered not expensive,” Charles said. “For us, that was a significant part of our budget.”

Related: Who should pay for preschool for the middle class?

To make more money, they rented out their basement, which meant sharing their kitchen. And Charles’ husband worked as a DJ on the weekends for extra cash. They were not eligible for income-based child care subsidies. Charles said the availability of public preschool, which has exceeded her expectations for quality, was a large part of their decision to stay in the city rather than moving to the otherwise cheaper suburbs.

“I think it should be available more places,” Charles said.

An expensive proposal

But for now, most children with working parents are not eligible for subsidized child care on any significant scale until the school year following their fifth birthday. The federal funding that does exist — about $22.2 billion — is meant to help poor families cover child care costs, but only 1 in 6 eligible families get the aid because there is not enough money for all of them. And that figure does not take into account the many families who earn more than 85 percent of their state’s median income and are therefore ineligible for federal help but are still unable to cover the cost of child care.

Now that middle-class moms are facing many of the same challenges low-income moms have faced for decades — unaffordable, unavailable or unsatisfactory care for their children while they must work to put food on the table — the needs of the two groups may be aligning in ways that could drive real change.

“This issue has come to a head in the last couple years because families can’t make ends meet with one full-time worker,” said Elise Gould, a senior economist at the Economic Policy Institute, a think tank. “People are beginning to realize that it’s not their fault or an inability to manage their own finances” that is making the cost of child care unaffordable for them.

Both Warren’s and Sanders’ plans would offer subsidized care to a broader swath of the public. On a smaller scale, so would the Child Care for Working Families Act of 2019, sponsored by Sen. Patty Murray of Washington and Rep. Bobby Scott of Virginia, both Democrats. The bill boasted 209 co-sponsors in the House and the Senate (including Warren, Sanders and Klobuchar), but has not made it out of committee.

All of these plans depend on the federal government spending significantly more money.

President Donald Trump has presided over one of the most significant increases to subsidized child care funding — more than $3 billion since fiscal year 2017. And though Republicans in general are supportive of expanding child care subsidies, the bolder of the Democratic plans — from Warren and Sanders — count on a new wealth tax that is unlikely to gain conservative support.

The Economic Policy Institute report that calculated current federal spending at $22 billion per year estimated that a national early childhood system that compensated caretakers in line with K-12 teachers and served all children from infancy to age 5 would cost $337 billion to $495 billion a year.

Warren’s plan, at an estimated cost of $1.07 trillion over the coming decade, would cost less on an annual basis in part because higher income families would pay a sliding-scale fee. Sanders has said his plan would cost $1.5 trillion over 10 years, but he hasn’t provided a detailed breakdown.

While most politicians have proposed incremental, less expensive solutions — the Child Care for Working Families Act has been priced at $40 billion a year — some experts say that more comprehensive plans are what’s needed to not only change the reality for working families but also to provide a needed jolt to the national economy. Offering subsidies to only the poorest families saves the government money, Gould said, but it “doesn’t get at the workforce issues for the providers or the parents.”

Increasingly, no one is left out of the delicate balance of how to afford having kids, ensure they are well-cared for, and work the hours necessary to make a living.

Jamie Smith is a lawyer by training but hasn’t worked full-time in law since her oldest, now 13, was born with severe disabilities. The mother of four said securing a place for her youngest, now 4, in her local public school’s preschool program in Washington marks the first time in more than a decade that she is able to contemplate saying yes to new work prospects.

“Up until this point, I haven't really been able to pursue a career, and I'm hoping that with these new opportunities, I'm on track to be able to do that now,” Smith said.

She and her husband, who works full-time as a lawyer for a union, live in Upper Northwest, one of the city’s more upscale neighborhoods. Still, private preschool was out of reach for them before their youngest son started public school this year.

“I absolutely would be willing to pay higher taxes, not just so that my own kids could attend pre-K,” she said, “but also to give the same opportunity to other kids and other moms.”

CORRECTION (March 2, 2020, 8:07 a.m. ET): An earlier version of this article incorrectly described data on preschool enrollment from the National Center for Education Statistics. In 2017, 68 percent of 4-year-olds and 40 percent of 3-year-olds were enrolled in either public or private preschools, not just in public preschools.

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