In the richest country in the world, the poorest among us are children.

Forty-two percent of African American children and 37 percent of Latino children are born poor – and they’re likely to stay poor. The 16 million children living in poverty suffer worse education, health and job outcomes, making it even harder for them and their families to break out of their circumstances.

In New York City, where nearly one-third of children live below the poverty line, Mayor-elect Bill de Blasio has pledged to tackle the pernicious problems of poverty and income inequality, and the centerpiece of his plan — to expand preschool to more low-income four-year-olds — is just plain common sense.

Studies demonstrate that kids who attend high-quality preschool achieve higher test scores, are less likely to go to jail and are more likely to secure good jobs with higher wages. Low-income kids of color, who are the least likely to have access to great preschools, benefit the most.

What gets lost in the hype about K-12 education reform, and the unhealthy obsession with things like standardized tests and charter schools, are a child’s crucial early years. Research from Stanford University shows that the gap in language proficiency between low-income and high-income children starts as early as 18 months and compounds over time as poorer children enter kindergarten less prepared than their wealthier peers and find it hard to catch up.

To stand idle in the face of these facts is to allow millions of children to fall behind in school before they even start. We can do better — and Oklahoma can show us how.

In 1998, a determined state representative, Joe Eddins, quietly pushed through a massive expansion of funding for full-day preschool, allowing both public schools and public-private partnerships to set up programs. Today, 74 percent of Oklahoma’s 4-year-olds are enrolled in preschool, and these kids are more than okay. The state’s early-education standards mean that class sizes are small, preschool teachers hold bachelor’s degrees and certification in early education and they earn as much as elementary and high school teachers.

These expert educators teach their young charges basic skills they will need to succeed in school — from how to hold a pencil to how to contribute in a group setting — and foster the kind of social and emotional development they need thrive in life.

The results are outstanding. A Georgetown University study found that in Tulsa, children who attended pre-K gained nine months on their peers in pre-reading and seven months in pre-writing — and the poorest kids experienced the biggest gains.

In a state where Republicans hold the governor’s mansion, state legislature, all congressional seats and every statewide office, universal preschool isn’t a partisan issue — it’s a point of pride.

Indeed, despite our country’s deep political polarization, there is growing support for expanding access to pre-K, from red states such as Georgia to blue cities such as San Francisco. In San Antonio, voters approved a sales tax increase to fund Democratic Mayor Julian Castro’s ambitious plan to expand preschool to more than 22,000 low-income 4-year-olds. In Michigan, Republican Gov. Rick Snyder’s budget calls for an additional $130 million over two years to expand access to the state’s Great Start Readiness program.

Even in Washington, where the two parties can barely agree on what day of the week it is, members in both houses of Congress have introduced bipartisan legislation that would give matching federal funds to states that develop quality preschool programs. Their effort gives form to an idea that President Obama proposed in his State of the Union address earlier this year (in which he praised Oklahoma).

The proposed legislation would cost $30 billion over five years — no small sum, of course. But that’s less than the $39 billion that taxpayers lost in the bailout. And it is less than the $32 billion for just half of the cost overruns from two years of faulty military contracts.

Despite the moral and economic stakes, America’s 4-year-olds still face an uphill battle against adults. Politicians pay lip service to the idea of preschool; the question is whether they will pay the bill. Look no further than the fury generated by what some called de Blasio’s “offensive” proposal to raise taxes on the richest New Yorkers to fund a preschool expansion.

What’s truly offensive is that in a city where the top 1 percent take home almost 40 percent of income, we wouldn’t be willing to invest a fraction of that wealth to ensure that all children — regardless of family income, neighborhood or background — have the opportunity to fulfill their potential.

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