In 1959, Baldessari began teaching art in the San Diego school system. He kept teaching for nearly three decades, in schools and junior colleges and community colleges, and eventually at the university level. When the University of California decided to open up a campus in San Diego, the new head of the Visual Art Department, Paul Brach, asked Baldessari to be part of the originating faculty in 1968. At UCSD he shared an office with David Antin. In 1970, Baldessari moved to Santa Monica, where he met many artists and Writers, and began teaching at CalArts. His first classes included David Salle, Jack Goldstein, Mike Kelley, Ken Feingold, Tony Oursler, James Welling, Barbara Bloom, Matt Mullican, and Troy Brauntuch. While at CalArts, Baldessari taught "the infamous Post Studio class", which he intended to "indicate people not daubing away at canvases or chipping away at stone, that there might be some other kind of class situation." The class, which operated outside of medium-specificity, was influential in informing the context for addressing a student's art practice at CalArts. He quit teaching at CalArts in 1986, moving on to teach at UCLA, which he continued until 2008. At UCLA, his students included Elliott Hundley and Analia Saban.