This series was designed to be useful in all teaching situations, from middle school on up. The range is limited to one octave - C to C - so that everyone sings in a comfortable range throughout. The flexible, modular design of this series allows you to concentrate on just the levels of complexity you want and adapt them for any kind of choir configuration. Ideal for use in a music curriculum spanning several grade levels. Beginning with stepwise, diatonic quarter notes, it's written polyphonically, so that every part is melodious and develops independence. Each exercise is written so that it can be performed in an unison, 2-part, or 3-part format. Since the lines of each exercise are interchangeable, each exercise can be sung three times, each voice singing a different line each time. The original volumes were available for treble clef choirs with a separate edition for bass clef singers and a combined version, but SAB, TTB and TBB versions were also added. Fully reproducible and available as a digital download, this reusable resource works year after year in a variety of formats.