At Brentwood, there are three levels of concert band.

Beginning Band is for students who are new to playing a band instrument. Basics of music reading and fundamental techniques for instrumental music are introduced in a structured class setting. Beginning Band performs three concerts during the school year and participates in solo/ensemble contest. Students are able to progress at an individual pace and are encouraged to become involved in extra music opportunities.

Intermediate Band is generally for students who have played a band instrument for a full year. In the second year of band instruction, students' further knowledge about music reading, instrumental technique, ensemble playing and performance practice. Intermediate Band performs four concerts during the school year, including a tour to elementary schools during the holiday season. Intermediate students are also able to become involved in extra performance opportunities such as jazz band, outreach performances, summer marching band, and solo/ensemble contest.

Advanced Band is generally for students who have played a band instrument for at least two full years. In the third year of band, students continue to further knowledge of more advanced music reading and develop more advanced instrumental technique. This includes varied opportunities such as auditioning for honor bands, participating in city-wide and regional honor groups, participating in summer marching band and summer jazz band. Advanced Band performs at least six concerts throughout the school year, including holiday tours and performances for veteran's ceremonies. Advanced Band students participate in CHSAA large group contest and have consistently received Superior ratings over the last 8 years. Advanced Band is the core of the Brentwood Jazz Band.

Jazz Band is for students who play a traditional jazz instrument (saxophone, trumpet, low brass and rhythm section). This is a director recommended group that has sixth through eighth grade students, based on ability level. The Jazzmanian Devils plays at many community events throughout the year including the Big Band Boogie Ball, Weld County Fair, community fundraising events, school events and assemblies, and the UNC Jazz Festival.

Choir at Brentwood is offered in every grade level and performs four concerts during the year. Choir is available to all students and may be started at any time during the middle school years. Extra performances include assemblies and the school wide musical.

Orchestra is offered in a similar setting to band at all three levels, beginning, intermediate and advanced orchestra. Intermediate orchestra participates in holiday tours and Advanced Orchestra also participates in CHSAA large group contest.