They are actually really easy and it doesn't take much fabric to make one. If you chain piece both quilts at the same time you can get them done rather fast. I did four tops at once in an afternoon/evening.
This is the actual pattern they send (or at least this is the only one I have seen them send.) you can make one just like it with VERY little fabric!
OOPs might have helped if I added the link!
http://www.quiltsforkids.org/images/...lt_Pattern.pdf