"Music Plus! was written to provide the student with great music that is enjoyable, accessible, and that sounds reasonably complete in two voices. It is playable in like instrument groupings, or with either or both of the other instrument voices. This collection is suitable for students with reading skills comparable to those completing the Adventures in Music Reading Book 3 by William Starr. The music presents challenges in rhythm, tonality (various keys), and musical expression and also serves as a music appreciation course, inspiring the student to want to hear the entire piece. William Starr has drawn the contents from various sources, including oratorio, opera, piano, and organ." - The Publisher.