The two big ones are 1/12 schale, the very small one is 1/48.
Method of making them is the same: very carefully!
The instructions by Jane Harrop are very clear, with a bit of care they are easy to do. I was wondering why I had wanted the small one when I got it, and saw how small the pieces are. You have to be careful with it, but it is doable. I must say I took twice as long to make the small one.
The one at the back does not have the roof glued on, I want to put a bird in it first.