For the past twenty years, Oaktown Jazz Workshops students between the ages of ten and eighteen have been learning the art of jazz by reading and by rote. “You have to be able to read music, and you have to be able to pick it up by ear. This music was originally passed on by oral tradition,” Khalil Shaheed, founder of the nonprofit organization, once stated. The trumpeter died two years ago, but his mission is being carried forward by bassist and current executive director Ravi Abcarian and a teaching staff made up of some of the Bay Area’s most accomplished instrumentalists. They include saxophonist Richard Howell, whose big tone and fierce attack on tenor suggest a John Coltrane-like spirituality. Howell, conguero John Santos, and groups composed of OJW alumni and current students will appear Monday at Freight & Salvage (2020 Addison Street, Berkeley).