Check out this entire line of books. These anthologies are a must have for every musical theater performer. The teen editions are great for young singers and for a little extra money you can purchase the accompaniment CD's which are an invaluable practice tool. Just look for your voice type and go from there!
This is a wonderful collection of anthologies compiled by Joan Boytim. I love these for teen singers as well as college aged students. You'll find lovely songs and arias in these collections and of course, every voice type is represented. I have the soprano anthology featured here, but be sure to find your voice type. These may also be purchased with the accompaniment CD's for rehearsal purposes.
Another great series for teens of classical songs and arias. Lovely, age appropriate, challenging pieces that will help young singers grow and learn!