Emma Shaw, a veteran early years educator and founder of Into the Woods, one of the UK's newest forest schools, explains where the idea came from.
"I was speaking to my Swedish neighbour in our communal garden and she told me about the Outdoor Kindergartens they have in Sweden... It sounded like a wonderful idea."
Yes, like so many of the recent passions of the chattering classes, forest schools originated in Scandinavia, where the philosophy of 'friluftsliv' or 'outdoor living' pervades the entire culture - including the region's attitude to education.
Since Sweden and Denmark established the first woodland schools in the 1950s, it has been common for Scandinavian children to spend all or part of their early years in the great outdoors.
The concept has also caught on in neighbouring Germany, where there are now more than 700 forest nurseries, or 'Waldkindergarten', in operation.
One of the newest UK forest school centres, Into the Woods, is a good example of how the forest school system works.
Nestled between two of North London's ancient woodlands, Highgate Wood and Queen's Wood, Into the Woods opened in April and now welcomes children aged between two-and-a-half and five for day or half-day sessions.
The toddlers meet in the morning, to 'kit up' in weather-appropriate, durable clothing, with fluorescent jackets to help their supervisors (one for every four children) keep an eye on them.
They then head out into the woods to a prepared 'base camp' - a length of tarpaulin strung up between branches to shelter the young students from rain and provide a focal point for group activities like snack time or singing.
And that's it.
For the rest of the day, they are encouraged to climb trees, dig holes, build dens, watch birds and animals and make up their own games. Adult intervention is minimal, with the nursery leaders offering occasional guidance.
Unlike conventional nurseries, set activities and regimented routines are de-emphasised. Children are encouraged to roam (all within the sight of their monitors) and get their hands dirty, enjoying a familiarity with nature that some fear is becoming lost.
Instead of plastic toy kitchens and action figures, toddlers improvise props from sticks, rocks, logs and leaves as they weave their playtime stories. Everything relies on imagination - a twig can be a fairy wand, a sword, a flute or a telescope.
But what of the Great British Weather? Well these real-life babes in the wood stay outside come rain or shine - only strong winds or extreme cold will prevent the troupe from making their daily excursion into the forest.
Into the Woods is the latest of a small growing tribe of forest schools in the UK, with increasing numbers of parents attracted to the social, physical and mental benefits of an outdoor education, as well as the 'return to nature' philosophy.
A 2003 study from the University of Heidelberg found that children who had attended a forest nursery went on to outperform their classmates in every developmental category in their first year at regular school.
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