Three novellas? More like two short stories and a novel, because the third story is way too long to be a novella.
Not on My Patch and How Lovely Are Thy Branches are cute little holiday-centered shorts, the first for Halloween and the second for Christmas. Not a whole lot to say about them, but they were fun and it was nice to see the kids hanging out and being friends without their lives in mortal peril.
Life Boats is entirely from Kit's POV, which is unusual and a nice change up from the shared POVs. Our friendly Earth wizards are off to help a planet evacuate before the planet's moon can fall apart and crash into it. So you know, no big deal. ;) Except that some of the planet's population don't seem able to or willing to leave, and no one can figure out why. This was not as terrifying a story as I thought it would be, given the world-ending premise, and it's wrapped up in a true YW way. There's a lot more hanging out, meeting and making new friends, and quite a bit of ... er, grown up talk as Kit and Nita are still figuring out their new relationship. I do like what this set of stories did for showing their friendship and how much their affections for each other have grown, and went some way to convincing me this is a good pairing and not just forced because of course the girl protag and the boy protag ALWAYS have to end up a couple.
I don't think I've mentioned it much, if at all, in other reviews for this series, because I was so wrapped up in the emotional hangover, but these NME editions are not the best edited. There are a lot of simple mistakes in the text throughout the series, and while the last couple of books have been much better, this one almost seems to be making up for those. Extra words, missing words, misplaced words - if the writing wasn't so strong, I'd be more annoyed by this, but I felt I needed to mention it at last.