St. Croix offers several musical groups. The choral and instrumental organizations give a number of concerts throughout the school year as well as compete through the Minnesota State High School League.
There are several extra-curricular opportunities, too, with rehearsals before or after school. Students who play the piano or organ may volunteer as accompanists during chapel. The Chamber Brass ensemble prepares selections appropriate for concert and worship. Jazz Band members enjoy preparing selections for concerts.
The Croixaliers are a select singing group chosen through auditions that perform at school concerts and many off-campus events at area worship services.