These little birdhouses are made from balsa wood. Most of them just have wood veneer for their roofs (rooves?) I had a strip of balsa wood left over from making my little garden so that's what I used. I painted them and then pushed a pencil in to make the hole, it worked surprisingly well. The tallest birdhouse is about 1 inch high.
And here's the vege patch for the garden. I need better 'dirt' but I'm really pleased with the way the wood around the patch turned out, it's just made from balsa wood too, painted with two different shades of grey paint. I think I've fallen in love with balsa wood this week!