I've discovered some incredible sites that offer printable paper crafts. These are not your average cut-and-fold giraffes or origami cranes; the ones I'm listing here are truly impressive. This craft is often referred to as "card modeling" because heavy cardstock is the preferred medium.
Many of these are highly detailed and labor-intensive, so unsuitable as a project for younger kids. I'm going to make some animals to use in finger plays, though, and some of the toy-making projects might be fun to use with the little ones. Here are my picks for the best, along with some other links I found along the way.
1. Canon 3D Papercraft: Just wonderful! Make pop-up cards, seasonal decorations, ornaments, animals, boxes, masks, or flowers. There is also a collection of 40 buildings and vehicles that can be used together to make a miniature town. Or choose to make some famous buildings or... or just go look, it's amazing!
2. Yamaha Motor: Yes, the motorcycle company. This Japan-based site (it's in English) features models of motorcycles, animals (like the macaw pictured above), and seasonal items. They are so breathtakingly realistic you may have trouble believing they're made of paper. Lots of work but worth it if you enjoy a challenge. (Nissan, not to be outdone, also offers some paper models of cars. This site is in Japanese, though, and the cars aren't nearly as real-looking. Honda also has some cute cars, but again - in Japanese.)
3. The Toymaker: Adorable, whimsical paper creations. Some are available in both color and black and white so you can save ink and color them yourself if you so choose.
4. Haunted Paper Toys: Perhaps a bit on the dark side for the younger kids, although the "Pocket Monsters" might be a fun one. There are some mechanical toys here, too, like a bat that flaps its wings when a handle is turned. Great detail, and perfect for Halloween decor.
5. Papertoys.com: Small, and not as detailed as some of the others - but relatively easy. A variety of vehicles and landmarks.
6. Mirkwood Designs: Tons of really nice printable templates for boxes, cards and envelopes. This doesn't quite fall into the "card modeling" category, but I like it so much I couldn't skip it in this list. I can see myself having the kids decorate these, and then doing the actual assembly myself. Older kids, say fourth grade and up, could do most of these unaided. In any case these designs would be wonderful as gift boxes or to hold holiday cards.
Other Sites to Check Out
HP Activity Center
Space Station 42