Goodreads https://www.goodreads.com/
Keep track of what your read, want to read, and finished. Also, see what your friends are reading.
Sparknotes http://www.sparknotes.com/
Provides study help for many subjects including literature and Shakespeare guides, preparation for SAT, ACT, AP Subject Test, and GRE, and online flash for biology, history, literature and SAT and ACT vocabulary.
Teen Read
Get reviews of books for teens, learn about authors and what books are coming out soon, and check out the Teen Ultimate Reading List. http://www.teenreads.com/
