The following year she raised funds for a rental collection of original works of art for students at Oberlin, including prints from older painters such as Rembrandt to more modern ones such as Picasso.

Over the years, it showed first the black-striped paintings that established Frank Stella’s reputation, and subsequently featured the work of Robert Rauschenberg, Joan Mitchell, Claes Oldenburg, Bruce Nauman, Chuck Close, Jackie Winsor and many other young artists.

In 1962 she wrote the first important article on Claes Oldenburg, and in 1970, with curator of modern art Athena Tacha, she commissioned his first permanent large sculpture (3-Way Plug) for the grounds of the Allen.

That same year she purchased the Frank Lloyd Wright-designed Weltzheimer house (1948–1950) in Oberlin, and spent a considerable part of her time and money restoring the building, where she lived the rest of her life.

Johnson's retirement from Oberlin College in 1977 was followed by an invitation to give the Power series of lectures in Australia, and by a visiting professorship at the University of California, Santa Barbara, in 1978.