[Note: I orignally reviewed the second edition of this course, but the third edition is now available. I do not expect that there are significant changes in the new edition.]
The University of Chicago School Mathematics Project (UCSMP) developed a series of texts based on the new math standards. Their Algebra text is reviewed elsewhere on this site. This Advanced Algebra text would follow algebra and geometry (in their sequence), serving as an Algebra II course. However, the scope and sequence is advanced beyond some other second-year algebra courses, including Saxon's. (Remember that Algebra II is the second in Saxon's high school series, so we must compare this text partially to Saxon's Algebra II and partially to Saxon's Advanced Math.)
Advanced Algebra is similar in design to the UCSMP Algebra course, incorporating practical application, mathematical thinking, and challenging skills. A scientific calculator is required, although a graphing calculator would be even better. Topics addressed are functions, variations and graphs, linear relations, matrices, systems, quadratic functions, powers, inverses and radicals, exponential and logarithmic functions, trigonometry, polynomial functions, quadratic relations, and probability. Explanations are better than in most texts at this level, so most students can work on their own. However, they should have a knowledgeable adult available for consultation if needed. You need both the student text and the teacher's edition, although ordering information for the teacher's edition is not up on the website.