This has a great layout, however it needs to provide more detailed instruction in the lessons. For example it does not teach how to convert the months so as to enable the student to fit the months into the equation. A teachers manual would be a good companion to this if it was available.
Finally...math that means something to the average person! My son was so annoyed with all the higher math, having to learn (memorize) so many things he'll never use. This book covers math in real life situations that you really do need to know.