Awesome. Foldschool is a series of free, downloadable patterns for making kids furniture out of cardboard. It's the work of Bern designer Nicola Stäubli, who seems be channelling the best aspects of the light-footprint DIY vibe of Papanek & Hennessey's Nomadic Furniture books. Here are some excerpts about the foldschool concept:

Mass culture is run by superficiality and ecological absurdity. Foldschool supports craftsmanship as a face-to-face approach to design and brings together product and user the closest possible.

The mindset of foldschool is to restore design to one of its original missions: to provide a product at an affordable price through a smart manufacturing process.

[from the faq re the choice of materials]: Cardboard is easy to find and easy to handle. Your kids can live out their creativity in painting on the cardboard. They will have their very personal piece of furniture. Once your kids have outgrown you can dispose of cardboard with a clear conscience.

There's a step-by-step manual, which helps you build a sample component before you graduate to the full piece. These look a bit involved and paper-intensive [the chair pattern runs to 54 pages], but also smart and fun.

foldschool cardboard furniture [foldschool.com via core77]
Previously: Nomadic Furniture 2 DIY Kids Boogaloo