This book is a Science Fiction Book Club special omnibus of five of Duane's YA novels: So You Want To Be a Wizard, Deep Wizardry, High Wizardry, A Wizard Abroad, and A Wizard's Dilemma. I'd previously read a couple of Duane's other YA books about wizards -- in which the wizards happen to be cats. This is the same universe, but the wizards are human teenagers. The wizardry is fairly interesting in these books, but I found the characters and the stories to be a little bit thin. It seemed to me that Duane was dumbing her writing down for the YA market. Which isn't to say that they were terrible; in fact, in places they were quite engaging, even thought provoking, but the writing was uneven and the whole package a little bit disappointing. Perhaps it was a mistake to read all five of them at once, but they came packaged in one volume.
Probably the most interesting thing about this universe is the quasi-religion that is the basis of wizardry. I'm sure the way that the books hint that Christianity is a badly garbled version of the quasi-religion would really honk off the fundies who think that stories about magic are the same as Satan worship. Frankly, I think the mythology and morality hinted at here would be a better basis for an organized religion than the Bible (or at least the accumulated weight of traditional interpretation the Bible has picked up in the last couple of thousand years), although what's found in these books is a little short on detail. But I'm not ready to convert; two of the basic points of dogma are that all the badness in the world flows directly from the will and works of one evil Power, and that the chief badness that Power brought into the world is death.
Overall, it's an interesting world to read about, and the stories go fairly quickly. Unfortunately, the plot and characters are awfully shallow in places. 7 out of 10.