When he needed a workspace on which to take down some notes, then-superintendent Rex Putnam rose from his desk and offered it to the young Duncan.

Duncan served in the United States Army, remaining active in the reserves, ultimately attaining the rank of colonel.

[4] Duncan began his teaching career in the Butte County Public Schools in Arco, Idaho, in 1954.

After his four-term tenure as Oregon's Superintendent of Public Instruction, Duncan returned to teaching in 1990, serving as dean of the University of Portland’s School of Education until 1996, when he took emeritus professor status.

[3][4] As a politician, Duncan took positions which placed him in the progressive or moderate wing of the Oregon Republican Party, as were many of his immediate predecessors and contemporaries, including the likes of Tom McCall, Clay Myers, Bob Packwood and Mark Hatfield.

[5] In a 2000 interview with The Oregonian, Duncan admitted to having voted personally for both Republican and Democratic presidential candidates, refusing to give particulars, but indicating that he was an enthusiastic supporter of George H. W. Bush but not his son.