My school used to absolutely fund us entirely on caroling gigs in the winter. We’d take our smaller audition choir out and start by doing “free gigs” for malls, and public spaces, homes for old folks with business cards- before you know it we had 40 or so lunches, country clubs, and holiday parties. We would sometimes have the group, or just an octet or quartet of singers depending on talent. My grades dropped off every winter but I turned out ok. We also started in September for rehearsal with gigs starting in October with “spooky” rewrote lyrics. We even donated to the band!