The Chorus is a co-curricular activity which is open to all students who are interested in choral music who are not already in the Band or Orchestra. There are four co-curricular Choruses at Kellenberg Memorial: 6th Grade Chorus, 7th & 8th Grade Chorus, Firebird Chorus for grades 9 and 10, and Phoenix Chorus for Grades 11 and 12. Chief among the activities of the Chorus are the Christmas and Spring Concerts, which are produced in conjunction with the Kellenberg Memorial Fine Arts Department. Members of the Chorus must be present at these concerts. In addition, the Chorus may sing at several community performances. Choruses perform both sacred and secular music of all styles and from many different cultures around the world.

Chorus practices are held every day as a regular part of the school schedule. Extended rehearsals are held according to a published schedule. Membership in the Chorus is contingent upon interest, cooperation, and singing ability. Since Chorus practices are held during the school day, members are free to participate in all after-school sports and activities. Vocalists may also participate in NYSSMA solo festivals and extracurricular groups such as the Fall musical and Jazz Chorus. Chorus members in grades 9-12 may elect to participate in the private lesson program in which students take weekly voice lessons scheduled during regular school hours. 

Students electing to participate in Chorus are committed to this program for one academic year. Students at the High School level are permitted to renew or discontinue their participation only in June for the following school year.