From Orion Magazine:
Urban, suburban, and even rural parents cite a number of everyday reasons why their children spend less time in nature than they themselves did, including disappearing access to natural areas, competition from television and computers, dangerous traffic, more homework, and other pressures. Most of all, parents cite fear of stranger-danger. Conditioned by round-the-clock news coverage, they believe in an epidemic of abductions by strangers, despite evidence that the number of child-snatchings (about a hundred a year) has remained roughly the same for two decades, and that the rates of violent crimes against young people have fallen to well below 1975 levels.
Yes, there are risks outside our homes. But there are also risks in raising children under virtual protective house arrest: threats to their independent judgment and value of place, to their ability to feel awe and wonder, to their sense of stewardship for the Earth—and, most immediately, threats to their psychological and physical health. The rapid increase in childhood obesity leads many health-care leaders to worry that the current generation of children may be the first since World War II to die at an earlier age than their parents. Getting kids outdoors more, riding bikes, running, swimming—and, especially, experiencing nature directly—could serve as an antidote to much of what ails the young.
More here.