I'm not sure of all of the years that she worked in that capacity but in the 1986 mock trial she identified herself as a "school psychologist." My understanding is that she became an administrator later on. Someone please jump in if that is not correct.
From "Mrs. Paine's Garage" by Thomas Mallon:
"After completing her master's degree [in psychology in 1980], Ruth spent the early and mid-1980s in the Florida Panhandle working as a psychologist in the Franklin County public schools. Mrs. Hyde [Ruth's mother] had passed away in '78 and both children had by now left home. Ruth returned to St. Petersburg in 1987 and took a job with the Hillsborough County school system [until 1995 when she retired]."
Mallon writes that it was during this period that Paine became active in opposing the Reagan Administration's policies in
Central America Nicaragua. She regularly attended the "Quaker Meeting" in St. Petersburg which organized food and other shipments of goods to Nicaragua in opposition/response to the sanctions placed on the Sandinista regime. Mallon wrote that she said she never liked the "shrill" nature of the anti-Vietnam War movement but she did resist making tax payments for a period during the war.
She had moved from Irving to Philadelphia in 1971 where she took a job as a principal of a small Quaker elementary school. The family stayed there until 1975 when her daughter Lynn's allergies forced a move to the warmer climate in St. Petersburg, Florida where the family lived for a period on a houseboat.