Diana Hanbury King, a master teacher who helped generations of students struggling to read fluently, write, and spell — and being stigmatized for it — because of an often undiagnosed learning disability called dyslexia, died June 15 at her home in Lakeville, Conn. She was 90.
Ms. King, whose uncle had dyslexia, taught, tutored, founded camps, and trained teachers in education programs that were replicated around the world.
“The time to diagnose dyslexia is before the child has a chance to fail at reading,” she said.
She was instrumental in transforming the popular perception of people with dyslexia from being backward or unteachable to being often highly intelligent, despite their learning difficulties. Often they were endowed with keen powers of observation and original thinking, innate charm, a sense of balance, and high energy.
“We continue to see the tragedy of a bright child coming home from school in the second or third grade in tears — ‘I’m the dumbest kid in all of the second grade’ — and getting stomachaches before they go to school, and all of this totally unnecessary and totally preventable,” Ms. King said in a videotaped interview with the International Dyslexia Association in 2013. “It drives me crazy.”
She said that dyslexia affects as many as one in five people and can be detected by age 4. (A child’s saying “washerdisher,” for example, can be symptomatic.)
But through intensive tutoring, she maintained — learning a few letters at a time, and integrating spelling and handwriting into their curriculum — students can pass standardized tests or even surpass their peers by the fourth grade.
“I am aghast at the lack of training teachers get,” she said.
Her own formal scientific training was limited to a botany course, but she developed an expertise in learning disabilities as a teacher at the private Sidwell Friends School in Washington.
There she had a number of mentors, including Anna Gillingham, a pathologist who pioneered methods of remediating difficulties in reading and processing language in collaboration with Dr. Samuel T. Orton, a neuropsychiatrist.
Ms. King wrote 15 books, including “Writing Skills” (1990) and “Never Too Late: Teaching Adults to Read” (2016), and was the subject of a 2014 documentary titled “One By One: The Teachings of Diana King.”
Diana Hanbury was born Sept. 2, 1927, in London to Anthony Hanbury, who worked in finance, and Una (Rawnsley) Hanbury, a sculptor.
In a 2014 interview with the founders of Camp Spring Creek in North Carolina, she recalled “those few moments when someone expressed confidence in me and my ability to learn.” She was 9 when a neighbor, a Royal Air Force pilot, taught her long division.
She earned a bachelor’s degree from the University of London and a master’s from George Washington University. Her marriage to James Cecil King ended in divorce, but they remained lifelong friends.
In addition to their son, she is survived by three grandchildren and her sisters, Jillian Poole, Anna Larkin and Josephine Coatsworth. A daughter, Sheila King, died earlier.
Ms. King spent time in Southern Rhodesia (now Zimbabwe) on her uncle’s farm, realizing only later that he and his daughters had dyslexia. By chance, she was hired as a teacher at Ruzawi, a boys boarding school, and immediately developed a passion for teaching.
After immigrating to the United States in 1950 and teaching at Sidwell, she became a naturalized citizen. In 1955, she opened Camp Dunnabeck in western Pennsylvania, offering a six-week program for children with dyslexia. She was soon stunned by how much they could progress in a matter of weeks.
“They never had to experience failure or feel they were stupid,” she said. “That one summer changed my life.”
Ms. King moved the camp in 1969 to Bucks County, Pennsylvania, calling it the Kildonan School after her uncle’s farm in Africa. She later transplanted it to Amenia, N.Y., 90 miles north of New York City, where the school continues to serve children with dyslexia and language-based learning disabilities year-round.
Ms. King also established a program for learning-disabled prison inmates.
She retired from teaching at 85. In 2016, she received the Lifetime Achievement Award from the National Teachers Hall of Fame.