Level Three of the Belwin 21st Century Band Method Series completes the curriculum for a three-year course of band. The third level book's format differs slightly from the previous levels to allow for longer exercises for the advancing students. It is also slightly more sophisticated in look for the older students. The third level delves into more major and minor keys and scales, changing keys, and more advanced rhythms and meters, including easy mixed meter pieces. Rock-style, jazz-style, specifically swing rhythms, and more syncopated rhythms are included. The book is divided into eight units, each introducing a new key signature.

After Units 2, 4, 6, and 8, selections are included for performance opportunities: full band, Duet Plus, solo with band accompaniment, and, after Unit 8, two full band commissioned pieces by well-known writers Carl Strommen and Mike Story. Popular songs include: The Magnificent Seven * Caravan * Proud Mary * Begin the Beguine * Pennsylvania 6-5000 * Take Five. Classical pieces, folk songs from around the world and American folk songs make playing in the band fun, as well as exposing students to many different cultures and styles of music.