Part library, part urban farm, part playground, this Farming Architects project in Hanoi is geared toward teaching kids about ecosystems and agriculture. The VAC Library’s climbable wooden structure contains both a small collection of books and a mini-ecosystem comprising a garden, a fish pond and a chicken coop—all connected through aquaponics. Waste from the koi pond is used as fertilizer to help vegetables grow, which cleanses the water and returns it to the pond. Chickens raised in cages within the structure provide eggs and waste that also help the plants flourish. Visitors can lounge and read the books stored in cubbies beneath the library’s solar panel-fitted roof, and children are welcome to clamber up its beams. —Mahita Gajanan