Jane Waldfogel is a professor at the Columbia University School of Social Work and an author of Too Many Children Left Behind.

Parents and babies turned out this week to support D.C.’s proposed 16-week paid parental leave legislation. (Jabin Botsford/The Washington Post)

Something remarkable is happening with parental leave.

First, in the tech industry, an array of firms have come forward in the past few months to offer what was a hitherto unheard of benefit in the United States: 16 weeks of paid parental leave, for both new mothers and new fathers (and even more, at one firm). Then the Navy announced that it was following suit for mothers. And now the District of Columbia looks set to become the first jurisdiction in the country to require employers to pay into a fund to provide 16 weeks of paid family leave, at 100 percent of pay for workers making up to $52,000 a year, and partial pay for those with higher earnings.

These policies stand in sharp contrast to existing laws and policies in most of the country. Two decades ago, the Family and Medical Leave Act broke new ground by establishing some rights to parental leave, but it is limited to 12 weeks of unpaid leave and available only to employees in medium and large firms. As a result, mothers in the United States continue to take much shorter maternity leaves than those in other countries, and fathers typically take a week or less. Three states (California, New Jersey and Rhode Island) provide some paid leave for new parents, but for only a short period (four to six weeks) and with only partial pay. Employees not covered by these laws might have some leave coverage, but this is strongly skewed by status and pay, with professional workers much more likely to have benefits than the low-paid. Against this backdrop, the idea of providing — or requiring businesses to provide — 16 weeks of paid parental leave to all employees looks nothing short of revolutionary, even if it’s still stingy compared to many European nations.

But will parents actually take more leave? If they do, will that matter to children? And how will employers cope?

For fathers, in particular, the recent developments could change how people think of leave. Fathers are notorious for taking mere days off after babies are born — helping out with a new baby and then rushing back to work. Although the evidence base on how fathers take leave is pretty slim, we do know that pay makes a big difference: Many households simply can’t afford the father taking time off without pay, either because the fathers are the primary breadwinners or because they are a low-income family that needs both parents’ paychecks. We know from California’s first-in-the-nation paid parental leave insurance program that offering paid leave increased leave-taking not just among mothers but also among fathers. And not surprisingly, the increase was largest among the lowest-income families, who can least afford unpaid leave.

Of course, even with paid leave, there are still barriers to parents’ taking more leave. Some employers might frown on parents taking as long as four months off, and employees might reasonably worry about the impact on their careers. So perhaps fathers might take just a week or two more than they do now, not the full 16 weeks. But even such a small increase would have an important impact.

My analysis of data from the nationally representative Early Childhood Longitudinal Study-Birth cohort shows that fathers who take longer leaves — two or more weeks, as opposed to less than two — are more engaged in feeding, bathing and other hands-on care activities with their children a year later. The same is true in a nationally representative British birth cohort study.

The evidence, then, is clear: Having dads around more at the time of the birth really does make a difference in terms of how involved they’ll be later on. We know that having more involved fathers is good for children, and also that having fathers more involved early on can set the stage for more equal sharing between parents down the road, which surely will help promote greater gender equity.

We also know that mothers who are offered more paid leave will take it, and that children benefit. The strongest evidence comes from Norway, where paid maternity leave led to reductions in the high school dropout rate. Studies examining leave extensions across a range of countries find that more paid leave leads to reduced infant mortality. Mothers who have access to more generous paid leave are also more likely to breastfeed, which has well-documented health benefits. From the perspective of an infant, there is a world of difference between having her mother or father home for 16 weeks and having them home for just four to six weeks, which is the length of time that most mothers in the United States currently take. And, of course, low-income mothers take even less, because they are less likely to have paid leave benefits and can least afford unpaid time off.

Stronger paid parental leave policies also have positive, long-term effects for children’s success in school. As research in my new book “Too Many Children Left Behind” shows, a student’s academic success in the United States is deeply tied to his or her socioeconomic status, far more than in peer countries like Australia, Canada and Britain, which offer up to a year of paid parental leave. More paid parental leave and other work-family supports could narrow the educational achievement gap in the United States.

Of course, it’s reasonable to ask how employers will cope with the costs of these new policies and how they will cover the work while new parents are on leave. But this looks to be a solvable problem. Clearly the tech firms are willing to tackle this. So is the Navy. Indeed, they have adopted these policies voluntarily, so they must see some benefits — especially in recruiting and retaining a better and more loyal workforce.

That we are now talking about providing 16 weeks of paid parental leave is remarkable. But it’s important to keep this in perspective: We still have a long way to go. The District of Columbia includes only a small share of the U.S. workforce (and some of those, such as federal government workers, will not be fully covered). And even with the state laws in California, New Jersey and Rhode Island, that leaves 47 states where employees have no entitlement to paid parental leave, unless they are lucky enough to work for one of the enlightened employers who offer it. So it will be important to build on the momentum from this summer and fall’s remarkable announcements — by tech firms, the Navy and now D.C. — and take the next steps toward providing at least 16 weeks of paid leave for all new parents. That goal now seems much more attainable.