The Teens Musical Theatre Collection can be great for working with a voice teacher on technique and getting some basic repertoire down, but for auditions most of the stuff in it is pretty overdone. I own the book and used it in lessons for several years and it was definitely a great book to get (especially for practice purposes since it has the accompaniment CD), but when looking for audition pieces I would try to find some others, though it is a great place to start for a beginner.
Another GREAT set of books to invest in are the Singers Musical Theatre Anthology books -- you can get them in Soprano, Mezzo/Belter, etc. There are (I believe) 4 volumes for each voice part with all the songs in their ORIGINAL KEYS, which is so great, and the rep in them ranges from very classic (Carousel, Oklahoma, etc.) to really contemporary (Light in the Piazza, etc.). It seems like a lot to spend when you first get them, especially if you get all 4, but they are an invaluable resource and great for lessons as well.
If your daughter is really into Musical Theatre, find her a good voice teacher who knows a lot about Classical technique (or whichever technique she chooses) AND Musical Theatre style, and you'll find these books are all very useful!
Best of luck to your daughter!
"grace, you're stuffed in a box getting rid of ass plaque. let's face it, this evening is a bust."