Welcome to this week's installment of “The green crib,” a series of posts where I focus on a single room in the home where an adult’s good green influence — and decorating sense — will ideally rub off on said room’s primary inhabitant: a little one.


So far in the series, I've featured eye-catching mobiles, earth-safe nursery cleaners, organic cotton quilts and blankets, not-too-cloying handmade wall art, low-energy lamps and night lights, and eco-trendy spins on two ubiquitous pieces of nursery furniture, the rocking chair and the changing table. Last week, I rounded up nursery odds and ends ranging from energy-efficient baby monitors to surfboard-shaped growth charts made from sustainable wood.


Today's topic hits particularly close to home as I was one of those kids who could spend hours on end creating — and then destroying — structures with a tub of old fashioned wooden building blocks before graduating on to more "advanced" building systems like, umm, Lincoln Logs.


That said, building blocks have come a long way since my days of erecting wooden shelters for my Playmobil figures. And although wooden blocks have always had an eco-upper hand on plastic toys, today's building blocks are more frequently made from sustainably grown wood, finished with nontoxic paints, or even made from non-wood materials like recycled PET milk jugs.


Below you'll find a few earth-friendly building block sets ideal for aspiring eco-architects. And if it's eco-dollhouses that you're after, click here to check out seven dollhouses that are decidedly more Ed Begley Jr. than Malibu Barbie. 


Haba Savilla Building Blocks @ Oompa ($69.99)















Green Toys Blocks @ Greeno Bambino ($25)















Plan Toys Eco-Friendly Unit Building Blocks @ Toys "R" Us ($64.99)















Beka Starter Block Set @ fawn&forest ($78)















Creative Blocks Set @ giggle.com ($34) 
















Citiblocks 50 Piece Cool Colors Block Set @ Oompa ($12.99)














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