Worm Farm/Ant Farm. this link has 20+ ideas of natural outdoor activities & alternative play structures. some simple & some pretty elaborate. mostly for younger kids. Outdoor Classroom, Ideas, Preschool Playgrounds, Worms Farms, Plays Spaces, Gardens, Outdoor Plays, Nature Playscape, Kids
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How to make a worm farm from recycled materials. Simple enough for kids to do. Teach kids about the superpowers of worms!