According to this BBC News article titled Nature deficit
disorder ‘damaging Britain’s children,’ the British are noticing
a change in the childhood experience. Researchers from the
National Trust are finding that the growing dissociation of
children from the natural world and internment in the “cotton
wool culture” of indoor parental guidance impairs their capacity
to learn through experience. They cite several reasons for the
decreased access to nature and child’s play outdoors: heavy
traffic and fears that automobiles do not see children playing
in the street, more focus on technology and toys that kids tend
to play indoors with (internet, TV, other toys), and parental
anxieties over crime and ‘stranger danger.’ Statistics found in
the study show that the area where children are allowed to range
unsupervised around their homes has shrunk by 90% since the
1970s. Access to play outdoors or interactions with nature help
children learn more effectively, and children themselves say
their happiness depends more o