(1) Sandra Day O'Connor, educated at Stanford both as an undergraduate and law student. At right is Justice O'Connor's official portrait (note the pink blouse), now hanging in the ground-floor gallery at the Court.
(2) As posted, Ronald Reagan nominated O'Connor in 1981.
(3) Reagan, a 1932 graduate of Eureka College in Illinois, is the last U.S. President not to have attended Harvard or Yale. This differently schooled President also nominated 2 others to the high bench who were not products of Harvard or Yale: Robert H. Bork (University of Chicago; Chicago Law) and Douglas H. Ginsburg (Chicago; Cornell Law). Neither was confirmed. In February 1988 the vacancy was filled by Anthony M. Kennedy (Stanford; Harvard Law), whom Justice Harry Blackmun (Harvard; Harvard Law) thus welcomed to his "good old no. 3" club. The 2005 nomination by President George W. Bush (Yale; Harvard MBA) of another person of diverse schooling, his White House Counsel, Harriet Miers (Southern Methodist University; SMU Law), also failed. (A chronology of all nominations to the Supreme Court is here.)
Bonus question: Charles Evans Whittaker, who served on the Court from 1957 to 1962, earned his law degree in 1924 from the University of Missouri-Kansas City. Whittaker served with the Court's next-most-recent-public-university-law-grad, Chief Justice Earl Warren (University of California-Berkeley). Appointing both was President Dwight D. Eisenhower, a graduate of the U.S. Military Academy at West Point, New York.