Circle of Friends Choirs, a community group that performs a mix of secular and religious music, will perform at 7:30 p.m. Friday at Grace Church, Harmony; 7:30 p.m. Saturday at St. Andrews United Presbyterian Church, Butler; 6:30 p.m. Sunday at St. Peter’s Lutheran Church, Evans City; 7:30 p.m. May 11 at Hope Lutheran Church, Cranberry Township; and 3 p.m. May 13 at Connoquenessing United Methodist Church. Admission is free but donations will be taken to support the designated charitable causes. Send e-mail to acofchoirs@gmail.com.

The Slippery Rock University Jazz Band will provide the music for the Harmony Business Association’s Derby Day in Harmony from 4 to 6:30 p.m. Saturday in the Harmony Museum’s Stewart Hall, 218 Main St., Harmony. Tickets are $20 per person and $35 per couple, and prepaid reservations are required. Admission is limited to those age 21 and older. Call 724-452-6220.

Union Junior and Senior High School concert bands will perform at 7 p.m. Wednesday at Union High School. The bands are under the direction of Lisa Hummel. Admission is free.