Policy aimed at promoting economic opportunity for poor children must be framed within three stark realities. First, many poor children come from families that do not give them the kind of support that middle-class children get from their families. Second, as a result, these children enter kindergarten far behind their more advantaged peers and, on average, never catch up and even fall further behind. Third, in addition to the education deficit, poor children are more likely to make bad decisions that lead them to drop out of school, become teen parents, join gangs and break the law.

In addition to the thousands of local and national programs that aim to help young people avoid these life-altering problems, we should figure out more ways to convince young people that their decisions will greatly influence whether they avoid poverty and enter the middle class. Let politicians, schoolteachers and administrators, community leaders, ministers and parents drill into children the message that in a free society, they enter adulthood with three major responsibilities: at least finish high school, get a full-time job and wait until age 21 to get married and have children.

Our research shows that of American adults who followed these three simple rules, only about 2 percent are in poverty and nearly 75 percent have joined the middle class (defined as earning around $55,000 or more per year). There are surely influences other than these principles at play, but following them guides a young adult away from poverty and toward the middle class.

Consider an example. Today, more than 40 percent of American children, including more than 70 percent of black children and 50 percent of Hispanic children, are born outside marriage. This unprecedented rate of nonmarital births, combined with the nation’s high divorce rate, means that around half of children will spend part of their childhood—and for a considerable number of these all of their childhood — in a single-parent family. As hard as single parents try to give their children a healthy home environment, children in female-headed families are four or more times as likely as children from married-couple families to live in poverty. In turn, poverty is associated with a wide range of negative outcomes in children, including school dropout and out-of-wedlock births.

It is sometimes said that Americans are turning their back on the marriage culture. The high divorce rate, soaring nonmarital birth rate and consequent rise of single-parent families are certainly weakening marriage as an institution. But look again and discover that college-educated women have high marriage rates, low nonmarital birthrates, and low divorce rates. The marriage culture seems to be alive and well for those with a college degree. These families usually not only have enough money to afford good schools for their children, but they also provide a stable family environment that allows children to flourish.

The recent attacks by Planned Parenthood on Michael Bloomberg, New York City’s mayor, for launching a campaign designed to inform teenagers of the consequences of teen pregnancy provides a good example of how many in our society face the effects of nonmarital births on teen mothers and their children. In one of the campaign posters, a baby with tears rolling down his face says: “I’m twice as likely not to graduate high school because you had me as a teen.” Another shows a girl saying to her mom: “Chances are he won’t stay with you. What happens to me?” Planned Parenthood criticized the ads, displayed in the subway and bus shelters, for ignoring racial and economic factors that contribute to teen pregnancy. Other critics say the ads stigmatize teen parents and their children.

Granted, most teen moms are from low-income families and face a number of barriers to success. Along comes Bloomberg with a direct message to get the attention of teenage girls and warn them not to make their situation worse and to think more about their future. If the mother wants to improve her future by continuing her education, being a teenage parent is precisely the wrong way to do it. As for blaming the victim, no one is blaming the baby—yet the baby will also bear long-term consequences.

Teenagers are capable of understanding principles and of using them to help make decisions. Anyone who delivers messages to teens about the consequences of decisions that could affect them and others for many years should be praised not criticized.

Bloomberg should next launch a public campaign about the value of marriage to adults, children and society. There will be at least as many critics of this message as the message that young people should avoid teen pregnancy. Good. The bigger the controversy, the more the media will cover the debate, and the more the nation will have the opportunity to reflect on what is at stake. I am confident that most Americans will conclude that organizations like Planned Parenthood have it wrong, and Bloomberg has it right.