Julio Cortez / AP

“Play has become a four-letter word.”

So says Kathy Hirsh-Pasek, a psychologist at Temple University and one of the authors of a new paper about the importance of play in children’s lives. The clinical report, published by the American Academy of Pediatrics, recommends that pediatricians write a “prescription for play” at doctor visits in the first two years of life. Years of research have shown that play is an important part of a child’s development, assisting in cognition, memory, social skills, and, to a lesser extent, maybe even mental health. Yet, according to the paper, children in the United States play less, and have less free time, than in decades past.

In the United States there has been much cultural focus in recent years on children’s academic skills and preparedness for college and the job market that awaits them as adults. No Child Left Behind, the 2001 act instituted by George W. Bush, encouraged classrooms as early as preschool to focus on structured activities meant to promote academic results—which, according to the report, led to “a corresponding decrease in playful learning.” In 2003, when the Bush administration reauthorized the Head Start program to aid low-income children, it removed a provision for evaluating the social and emotional skills of children who participated relative to their peers. The authors of the report argue that downplaying such nonacademic development could limit children’s attention spans and degrade their behavior in the classroom.

“When children have an opportunity to play, and move, it does enhance their learning and their behavior,” says Pooja Tandon, a pediatrician at Seattle Children’s Hospital who specializes in play and was not involved in the report. “Some of the emphasis on pre-academic skills or more traditional forms of learning, they have squeezed out play from childhood.”

Tandon is interested in two particular forms of play, outdoor and active, which she says lead to better academic outcomes and, for older children and adolescents, documented benefits for mental health. A Canadian study published in the Journal of Adolescent Health found that when teens play sports, they experience fewer symptoms of anxiety and depression as young adults. And a 2011 meta-analysis looking at exercise—an important component of active play—hinted that it could have benefits for anxiety, depression, and self-esteem in adolescents.

“I think we’re a culture that tends to reduce everything to IQ and cognition,” says Michael Yogman, an assistant clinical professor of pediatrics at Harvard Medical School and the lead author of the new report. “One of the things that we’re learning is that adult success is at least as much related to social and emotional skills and executive function as it is to cognition … If you notice, we didn’t emphasize a lot about the effects of playful learning on cognition” in the report. Instead, Yogman says, the authors chose to focus on children’s social development, mental health, and “enhancing the parent-child relationship.”

Much of the research to date on play and mental health consists of animal studies (which, the report cautions, can’t be directly interpreted as evidence of human behavior). Studies have shown that young rats that were socially isolated during “peak play periods” are less social later in life. Lots of time to play is associated with low levels of cortisol, a stress hormone, in monkeys; as Yogman, Hirsh-Pasek, and their co-authors argue in the report, play may reduce toxic stress and cultivate resilience and coping mechanisms.

Sharon Hoover, a co-director at the University of Maryland’s Center for School Mental Health who was not an author of the report, agrees that mental health and play appear to be connected. Play can “promote positive feelings like joy and excitement, which can bolster mood and diminish anxiety and sadness,” she says. Meanwhile, insufficient playtime has been shown to increase symptoms of depression, anxiety, inattention, and conduct problems in students, she says.

The paper concludes that pediatricians should stress the importance of adequate playtime to parents, educators, and policy makers. In one national survey, only 51 percent of preschool-aged children went outside with a parent to walk or play each day. The report also notes that so-called enrichment activities, as well as rising homework loads and preparation for tests, often take priority over play.

For children in poverty, those challenges are even more difficult to overcome. “It’s important to emphasize the likely disparities in opportunities for play and access to play for children depending on their family situation, their community, and their zip code,” Tandon says. “Those of us in public health, as health-care providers, as teachers, and as parents, may have to be really intentional in thinking about play as a right for all children.”

Tandon also notes that children in poverty might benefit from play the most. She cites research that has found that giving children plenty of time to play can strengthen coping mechanisms and reduce stress. Yogman agrees, saying that when children play with their parents, the parent-child bond is strengthened. That, he says, “translates into better relationships that can buffer adversity.”

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.