Dealing with the threat that growing inequality in the United States presents to the country's economic and social well-being has in the past few years become the background for almost every policy discussion, from health care to international trade deals.

But Republican presidential candidate Jeb Bush called the problem by a slightly different name in a speech in Detroit in February. In his first major policy speech after hinting he was considering a presidential run, Bush said that "the opportunity gap is the defining issue of our time."

Equal opportunity, that most treasured attribute of what makes U.S. society work, is under siege, according to this view. And one recent book by Harvard sociologist Robert Putnam distills the problem as one created by polarized ends of a spectrum of parenting. Briefly, "Our Kids: The American Dream in Crisis," argues that families that shower their children with time, attention, and resources produce kids who maintain and even improve on their parents' socioeconomic status, while families that lack resources or the stability to provide them see their kids fall down along the way, from early schooling to adulthood.

Unsurprisingly, these two types of parents sit on different sides of the class divide, with those in the middle class and above multiplying their advantages across generations, and those among the working class and the poor cementing their immobility. In an event in Washington last month, Putnam said that by the time kids begin formal schooling, the die has largely been cast.

"The rich kids bring these parental resources in their backpack and they bring parental aspirations and they bring a lot of other good things," Putnam said. "And poor kids [...] bring gang violence and family dysfunction and so on. Those things are bad for their fellow students and the increasing concentration of kids in either low-income or high-income schools has really important consequences."

Having consistent nurturing from reliable adults makes a big difference too, as does playtime. What these practices have in common is time and focus, scarce commodities for low-income and poor parents dealing with economic insecurity about their jobs, their ability to retain housing, their relationships, and even where their next meal will come from.

But the more revealing conclusions in Putnam's argument, and the ones that policymakers have started to latch on to, have to do with how early these differences begin to manifest—long before kids, rich or poor, step into school.

Public and private decision-makers are listening. Foundations are pouring more money into interventions to help low income parents support their preschool children. Elected officials are advancing ideas from the ACA-funded home visitation program funding for pre-school programs in both red and blue states.

In the next few weeks, Next America will highlight how some of these ideas to expand opportunities for kids by providing their parents with the right tools are being tested—and which are already showing promise.

Refocusing on parents and their actions as the foundation for educational and economic success appeals to policy-makers across the political spectrum because it involves both doctrines of personal responsibility and large-scale service-providing programs.

Citing research on the development of young brains, Putnam zeroes in on the verbal interactions between preschool children and their caretakers as the first of several compounding differences between kids who do well later in life and those who face greater obstacles.

Dubbed the "word gap"—a difference of 30 million words in exchanges between wealthier children and adults by age 3, compared with the number of interactions in poorer families—has become one measurable, clear point of inflection to tackle inequality before it sets in.

Already, the "word gap" has produced several prominent and well-funded responses. Four of these efforts received over $11 million in foundation funding in the past year alone.

A June 2014 conference sponsored by the White House gathered the biggest players in the field, including the Too Small to Fail initiative funded by the Clinton Foundation and an effort run out of the University of Chicago School of Medicine aptly called the Thirty Million Words Initiative. The Obama administration pledged $2 million to the National Academy of Sciences for a study to find the best practices to apply to kids who speak languages other than English.

Having consistent nurturing from reliable adults makes a big difference too, as does playtime. What these practices have in common is time and focus, scarce commodities for low-income and poor parents dealing with economic insecurity about their jobs, their ability to retain housing, their relationships, and even where their next meal will come from. Research shows that parents with means spend much more time with their kids than those with less during the crucial developmental period before they enter formal schooling, and that the effects magnify over time.

A 2013 study by Kimberly Howard and Richard Reeves of the Center for Children and Families at the Brookings Institution found that the children of parents who provided the least cognitive stimulation and emotional support had worse outcomes in educational achievement, income, and avoiding life events that depressed their situation, such as having kids early in life or ending up with a criminal record. And the benefits increase over time.

There is some evidence that the situation can be improved. Howard and Reeves found that helping the parents with the least resources can improve some of their practices, and bringing them to the level of what parents with average means did made a meaningful difference. Of the children whose parents made positive changes, 9 percent more graduated from high school, 6 percent fewer had kids of their own by age 19, and 3 percent fewer had criminal convictions by 19.

But what are the best interventions to help parents take up the practices that will make them better at preparing their kids from the start?

One approach that's been tested is to have home visits to support parents-to-be and new parents. A federally funded program, created as part of the Affordable Care Act, that sends nurses and other health professionals into the homes of expectant and new mothers was renewed in April for $400 million over two years.

Other approaches involve group workshops that connect parents of young children to each other and to practices that support their children's cognitive development. And others even use technology to address the "word gap."

The main challenge for many of these projects is that they require one-on-one interventions over several years, with the attendant personnel and funding. And none really address the disruptions to stable families caused by forced job mobility, incarceration, or addiction.

And the data to support the efficacy of these programs is just starting to come in, just in time for the ramp-up to the 2016 presidential race. A study of home visitation programs for young mothers found that they were more likely to continue school, and showed improved parenting. And a team at the University of California, San Francisco is following what's happening in a program started last year in two hospitals in Oakland, California, that has pediatricians provide parents with information on how to improve early literacy.

Overall, investing in parents to help them interact more meaningfully with their infants shows the potential to come closer to leveling the field for poorer kids when they enter school.

This story is part of our Next America: Early Childhood project, which is supported by grants from the Annie E. Casey Foundation and the Heising-Simons Foundation.

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