He returned to the University of Illinois Urbana-Champaign, studied composition with Salvatore Martirano and composed for the college jazz band led by violist John Garvey.
In 1968, Knapp's rotary-valve flugelhorn solos and composition "Medley" were noted at the Collegiate Jazz Festival (CJF).
In 1977, when Joe Field left Seattle, Knapp renamed the group the Composers and Improvisors Orchestra (CIO) and made it the Cornish group-in-residence for eight years.
Guest artists included Gil Evans, Carla Bley, Sam Rivers, and Anthony Braxton.
[5] Cornish gained full accreditation in 1977 and Knapp assembled a jazz faculty that included bassist Gary Peacock, vocalist Jay Clayton, drummer Jerry Granelli, saxophonist Denney Goodhew, and trombonist Julian Priester.