Short answers, pulled from the story.
SLATE was a campus political party at the University of California, Berkeley, active from 1958 to 1966. It is described as a pioneer organization of the New Left and a precursor of the Free Speech Movement. The name stood for a slate of candidates running on a common platform.
SLATE was formally established as a campus political party in February 1958. It voted to dissolve itself in October 1966 after a proposed student government constitution was voted down in a referendum in April 1966.
The name was not originally an acronym; it simply meant a slate of candidates on a shared platform. When the Daily Californian refused to print a non-acronym in all-capitals, SLATE declared its name an acronym for "Student League Accused of Trying to Exist."
SLATE supported racial equality, free speech on campus, voluntary ROTC, and a Berkeley fair housing ordinance in 1959. It opposed the House Un-American Activities Committee, the execution of Caryl Chessman at San Quentin, and continued nuclear weapon testing.
The Free Speech Movement emerged in the fall of 1964 over the right of students to place tables at the campus entrance for off-campus causes, the issue SLATE had promoted since its founding. SLATE members were active in the FSM but generally were not its leaders, and the FSM coalition was even broader, including Young Republicans and Barry Goldwater supporters.
David Armor was SLATE's first and only student body president, elected in the spring of 1959. Later figures connected to SLATE included Jackie Goldberg, who served in the California Assembly from 2002 to 2006, and Bill Lockyer, who served as Attorney General of California from 1999 to 2007 and state Treasurer from 2007 to 2015.