What is JASS? (pronounced jazz) 1. (noun) Youth, families, and choirs who join together in the afternoon for fun, fellowship and music. Hey, we’re going to JASS today! 2. (verb) The fun participation in JASS. We’re jassin’! JASS includes choral groups for kids in Kindergarten through senior high, bell choirs for kids in grades 4 through 12, a…