Word Spy - free-range kid

free-range kid n. A child who is given lots of time for unstructured activities and play during the day. Also: free-range child.

Example Citations:

In his new book Under Pressure: Rescuing Childhood from the Culture of Hyper-Parenting, Canadian philosopher and writer Carl Honoré wrestles with his own well-intended overparenting and taps into a number of schools and families inspired by the free-range child. ...

Elsewhere, Mr. Honoré documents outposts of free-range kids around the world and finds them flourishing. He cites an outdoor nursery called The Secret Garden in Scotland where kids can run free.

"It brings together so many of the anxieties and problems we're talking about and it seems to solve them in one fell swoop."
—Tralee Pearce, "The free-range child," The Globe and Mail, May 13, 2008

Most of the time when a baby cries, they are tired or attention- seeking. In both cases, ignore them, she insisted. That sounds very harsh, but Verity is only updating a method of child-rearing from the 1950s, as espoused by a New Zealand doctor, Frederic Truby King, which was based on the belief that children who are subject to a strict routine are more likely to thrive than those who are not those my mother refers to dismissively as free-range kids.
—"My best-for-baby formula," Irish Examiner, May 1, 2008

Earliest Citation:

The series, which pits a space cadet witch (Corinne Bohrer) against a luckless divorced lawyer (Frank Luz) and his three free-range kids, settles into a regular slot on both stations next Saturday at 7.30 p.m.
—Greg Quill, "Heartwarming Family Matters," The Toronto Star, September 22, 1989

Notes:

Allowing one's children free time is called, not surprisingly, free-range parenting, a phrase that dates to 1999:

Like his audience, Sandler is growing up, and "Big Daddy" is his version of "Parenthood."

Sandler plays a slovenly underachiever who inherits a 5-year-old boy. The boy's mother is dead and Sandler is mistaken for his birth father. Initially, he likes the idea of having someone to play with. He teaches him the bad habits he has refined over a lifetime — spitting, tripping in-line skaters, gorging on junk food — and uses the kid as bait to attract women. ...

Because his own father, played by Joe Bologna, was too strict, Sandler practices free-range parenting, letting the kid dress as he likes, urinate in public and go unbathed.
—Duane Dudek, "'Daddy' Sandler not growing up very fast," Milwaukee Journal Sentinel, June 25, 1999

If you want to know more about free-range kids, the place to go is Lenora Skenazy's Free Range Kids blog.