kim lau ten takes a look at the mission that is more than music. >> it's a century of celebration. >> for the past 100 years, they put on a christmas concert that is known and loved around the world. nearly a third of the 3,000 students participate in the christmas festival, which combines more than 600 voices from five campus choirs, including the elite st. olaf choir. the repertoire showcases a variety of sacred music. there are classic holiday standards, songs that hark back to the school's scandinavian heritage, and some from other cultures as well. the program is designed to reflect the essential religious meaning of christmas. anton armstrong conducts the st. olaf choir. >> it's just not the music, but that we are lifting up a message, a message of hope, a message of faith, a message of understanding, and most of all a message of love. >> the popularity of the christmas festival has gone global. for decades, it has been broadcast on public radio and public television, and the armed forces radio and tv service as well. this centennial concert was also simulcast in movie-theaters