William Ballard
William Ballard, name-checked as "Mr. Ballard" on the cover of "Freak Out!" (1966) under the heading "These People Have Contributed Materially In Many Ways To Make Our Music What It Is. Please Do Not Hold It Against Them", was the high school music instructor and band director at Antelope Valley High School. He allowed FZ to conduct the school orchestra a couple of times. He also let him write music on the blackboard, and had the orchestra play it.
He is also mentioned "The Real Frank Zappa Book" (1989): "Mr. Ballard also did me a big favor without knowing it. As a drummer, I was obliged to perform the gruesome task of playing in the marching band. Considering my lack of interest in football, I couldn't stand sitting around in a stupid-looking uniform, going 'Da-ta-da-da-ta-ta-taaaah; CHARGE!' every time somebody kicked a fucking football, freezing my nards off every weekend. Mr. Ballard threw me out of the marching band for smoking in uniform -- and for that I will be eternally grateful."