In Denmark, a remarkable concept for schooling young children is growing ever more popular. Called ‘forest kindergartens’, these unusual schools trade classrooms for the great outdoors, where pre-schoolers are allowed liberties that many parents would consider dangerous. These tots slide down muddy slopes, climb trees, and are taught how to use knives from an early age.

“It’s important for young children to learn what it is to be cold, what it is to be wet, and survive that,” says Jane Williams-Siegfredsen, outdoor education specialist. By abandoning the traditional classroom in favor of an untamed forest, instructors at these forest kindergartens are able to teach things that children couldn’t learn anywhere else, like knife skills. Is it unsafe? Rather than “wrap children in cotton wool,” as Williams-Siegfredsen puts it, she would have children learn for themselves how to be safe.

The concept is taking hold in Denmark, where 10% of all kindergartens are forest kindergartens. There are now a few forest schools outside Denmark, but the rest of the world may be resistant to the idea of giving such young kids so much freedom and responsibility. For example, when KnivesShipFree owner Derrick Bohn offered to send free knives to kids through his Knives For Kids Program, he was met with an immediate backlash from concerned parents – one even accused him of trying to “arm children with knives.”

Why Denmark? “One of the big things that I see here is the amount of trust that there is in Denmark,” says Williams-Siegfredsen. “There is no formal inspection of kindergartens. There is no one who comes round and checks up on what we’re doing, what we should be doing.” Danish parents who send their children to these forest schools trust that their children, with gentle guidance from their instructors, will learn and grow in a way they couldn’t in a traditional kindergarten. “They see it in a different way,” says Williams-Siegfredsen. “That in fact children should have the chance to be free.”