We are using "Complete GED Perparation" in our free GED preparation classes because they are easy to use as a text book. 1. The introductory exams are not too long and give the information on the needs of each student. 2. Answers to the intro exams are given with explanation that will help the student. Normally no more explanations are needed. 3. If more information is needed, the text for each subject is easy to understand. 4. A sample exam is toward the back of the book that will allow the student to practice on an exam that will simulate the real thing. All in all, I cannot conceive a better arranged or more concise source for GED preparation.