Wind Ensemble - The Wind Ensemble is the top performing band in the Klein Oak Band program. It is comprised primarily of seniors and juniors who have achieved the highest level of musicianship in the program. Members of this band perform in the marching band and participate in a variety of other musical activities. They are expected to participate in the All-Region Band / All-State Band audition process. They are assigned to chamber ensembles and are expected to participate in the KISD Solo and Ensemble Contest. They may also choose to participate in UIL Solo and Ensemble. This band represents Klein Oak High School as the varsity performing group at UIL Concert and Sightreading Contest as well as at any other competitive performances. Individuals are also selected from this group to form the wind and percussion sections of the Full Orchestra and to accompany the school musical as members of the "pit orchestra". The emphasis in this performing group is on advanced individual musicianship and ensemble performance.

Symphonic Band - The Symphonic Band is the second performing band in the Klein Oak Band program. It is comprised primarily of juniors, sophomores, and advanced freshman musicians. Members of this band perform with the marching band and participate in a variety of other musical activities. They may elect to participate in the All-Region Band / All-State Band audition process. They are assigned to chamber ensembles and are expected to participate in the KISD Solo and Ensemble Contest. They may also choose to participate in UIL Solo and Ensemble. This band represents Klein Oak High School as the non-varsity performing group at UIL Concert and Sightreading Contest as well as at any other competitive performances. The emphasis in this performing group is on developing individual musicianship and ensemble performance skills.

Concert Band - The Concert Band is the third performing band in the Klein Oak Band program. It is comprised primarily of sophomores and freshmen musicians. Members of this band perform with the marching band and participate in several other musical activities. They are assigned to chamber ensembles and are expected to participate in the KISD Solo and Ensemble Contest. They may also choose to participate in UIL Solo and Ensemble. Members of this band do not participate in the All-Region Band / All-State Band audition process. This band represents Klein Oak High School as the sub-non-varsity performing group at UIL Concert and Sightreading Contest as well as at any other competitive performances. The emphasis in this group is on developing individual musicianship and ensemble performance skills.

Varsity Band - The Varsity Band is the fourth performing band in the Klein Oak Band program. It is comprised primarily of freshmen musicians. Members of this band perform with the marching band. They may elect to participate in solo and ensemble contests but do not participate in the All-Region Band audition process. This band does not perform competitively but does participate in concerts and other non-competitive performances. The emphasis in this group is on basic individual musicianship and ensemble performance.

Fundamentals of Instrumental Music - This is a non-performing, non-competing class that focuses entirely on building individual musicianship. It is comprised exclusively of freshmen. Members of this class do not participate in marching band. Members of this class have multiple opportunities to audition for placement in a performing band and will be reassigned at the first available opportunity after demonstrating the necessary skills to advance. Membership in this class is limited to one year. If a student does not progress sufficiently to be placed in a higher band at the end of one year they will be removed from the band program.

Jazz Band - Jazz Band is a performing group that meets daily. Membership is limited to jazz band instruments only. Jazz Band members must be currently enrolled in band, choir or orchestra. Jazz band performs several times each year and attends a Jazz Festival in the spring.