Algebra is a skill, according to this author, and as such, is best learned through repeated practice over an extended period of time. Unlike texts which treat a topic in some detail before moving to the next, Saxon's 126 lessons break a concept down into small units so that each may be practiced thoroughly before the next part of the same concept is introduced. When all these smaller units have been presented, the topic is not "finished" but is constantly reviewed. Thus, in a given problem set, the student can expect to find exercises covering not only the present lesson, but any previous material as well. "If you find that a particular problem is troublesome, get help at once," warns the author in a note to the student, "because the problem won't go away. It will appear again and again in future problem sets." In his preface, the author refers to a research experiment monitored and certified by the Oklahoma Federation of Teachers which was designed to test the effectiveness of this text. It was found that students using this book more than doubled the scores of students having the same teacher but using a standard book. On selected topics, the Algebra I students using Saxon's text more than tripled the scores of Algebra II students not using it. (MM)