Under Their Skin by Margaret Peterson Haddix
My rating: 3 of 5 stars
Because this is Haddix, it's understood that there will be a twist of some sort; what pleased me was that I didn't quite expect this twist (my initial thoughts were more along the VC Andrews' lines - is it too much of a spoiler to say I was wrong?). And, of course, this is part of a series so the answers aren't all there... yet. There are parts that were less plausible than others, but teen readers may not notice. Nor, I suspect, will they have read as many other books of this type so that once the surprise twist happens, there is a sort of a letdown because, well, the rest felt predictable.
ARC provided by publisher.