This is a very good idiom book because it provides definitions, examples, memorable illustrations, and practice. The practice consists of dictations, self-reflection on what you learned or didn't understand, discussion questions, dictation, skit writing and improvisation. Oh, and there are review games (crosswords, tic-tac-toe, and guess the idiom) after every four lessons. There are 12 lessons and an alphabetical index of the 300 idioms taught in the book. 

The one problem for me is that this book is almost too rich in idioms. Rather than using it as a textbook, I like to use one lesson at a time as a supplement for an advanced class. Then the students and I pick out the most useful idioms to study and practice. 

The cassette/CD apparently contains readings of dialogs given in each lesson; some dialogs have fill-in-the-idioms-listed-above blanks, so they would make good listening exercises. (The answers to these listening exercises are in the back.) The audio also has dictations (scripts are in the back too). If you have a tight budget, the book is fine without the cassette.