Thelma Yvonne Cones, 56, a former reading specialist in the D.C. public schools and then at the George Washington University Reading Center, died of cancer Thursday at Washington Hospital Center.

Mrs. Cones, who was born in Trenton, N.J., first came to Washington to study at Howard University, from which she graduated in 1944. At the same time, she worked at the Navy Bureau of Ships and was elected "Miss Bureau of Ships" one year.

She earned a master's degree at Pennsylvania State University in 1945, and then taught home economics at Florida A&M in Tallahassee for a year. She returned to Washington in 1947.

She began her career in the D.C. public schools in 1957 and continued until 1971. She spent most of those years at Bunker Hill Elementary and Kelley Miller Junior Hight.

She was a reading diagnostician at the George Washington reading center. She had continued private tutoring in her home since then.

Mrs. Cones had been a Red Cross volunteer at the occupational therapy workshop at the Soldiers' Home Hospital in Washington, and a volunteer in the A.K.A. sorority tutoring program at Slowe Elementary School and in the D.C. Right to Read Program.

She was a member of the International Reading Association, the Elementary-Kindergarten-Nursery School Educators Inc., and the Howard University Alumni Club. She also was a member of Calvary Protestant Episcopal Church in Washington.

Survivors include her husband, Kenneth L., a retired D.C. police lieutenant, and a daughter, Joyce, both of the home in Washington; a son, Kenneth L. Jr., of Arlington, and her mother, Estella Thomas, of the home.

The family suggests that expression of sympathy be in the form of contributions to the Howard University Scholarship Fund in the name of Thelma Thomas Cones.