Grace Vandendool's thorough approach to keyboard theory offers students easy-to-understand lessons and plenty of reinforcement activities. The progressive Preparatory Series and Theory Series include visual aids that strengthen the connection between theory and practice, laying the groundwork for success in the study of harmony. The Keyboard Theory Preparatory Series, 2nd Edition is ideal for elementary-level students (aged six to nine). This progressively levelled five-volume series teaches the fundamentals of music notation and supports any beginner piano method. Book D introduces whole tones; key signatures; minor keys, intervals, and triads; harmonic minor scales; simple time; transposition; Italian terms; and analysis.