Ruth Fenner graduated from the Sydney Kindergarten Training College, and is best known as the host of The Kindergarten of the Air on Australian radio. In October 1946, she spent six months in the United States, studying at Columbia University and speaking to the Federal Radio Education Department in Washington, followed by a period in the United Kingdom. She returned to Australia in later 1947.
In 1950, after seven years on the former show, she also began hosting Prayer and Praise for Little Children.
She married Bruce Plummer in Sydney in 1950, but continued working for some years.