Secret upon secret in this page-turner

I could NOT put down my copy of Four Secrets by Margaret Willey!  Katie, Nate, and Renata are all in the juvenile detention center - they're in a ton of trouble for kidnapping Chase, the star athlete at their school and a major bully.  The story is told both through the journal entries they're required to make (three very different styles) and through a narrator who describes social worker Greta and her attempts to put together the pieces of a very confusing puzzle. It's obvious that the three have made a pact to not give away something huge; it's also evident that each has a serious secret.  And so does Chase.  And you'll go nuts trying to figure them out, and you won't know everything until the end of the book.  (Don't peek!) The ending is a bit rushed and not 100% satisfying, but still...I dare you to read this slowly.