I just used this book to teach an introductory music theory class for adults (primarily community members with a recreational interest in playing/knowing more about music). I must say I was very pleased with this book in general. It offers straghtforward theory lessons with appropriate drills for getting a grip on the content. This is not an in-depth tome by any means, but it worked out well for my purposes.
I have the following minor gripes:
-This is really three books spiral bound together as one. A combined table of contents would have been most welcome.
-The CDs with the listening examples are not included and it seems the only way to acquire them is to buy the answer key book at almost $40. Phooey. How about offering the CDs with the student book for an extra $10?
-I don't care for the way this book teaches the compound meters 3/8 & 6/8. The method used is very practical and straghtforward, however, so it works out okay. It just never mentions 'compound' or 'simple' in presenting meters.
-9/8 & 12/8 are not presented. Ever.
-No asymmetric meters are presented. Ever.
With all of that out of the way, I'm happy to recommend this book for your middle school level band kids or even high school students looking to pick up some written theory, and of course as I used it for your bare-bones beginning adults with an interest in the subject.
A motivated student with the listening CDs could run through the course on his or her own, but I think you really still need a teacher for best results. Particularly as this book lacks the depth of background and explanations that an engadged student will inevitably be curious about.