James Gregory Slaughter, 70, of Cedarbrook, a retired Philadelphia School District principal, died Sunday, June 9, of respiratory failure at Chestnut Hill Hospital.

Mr. Slaughter was the elder of twin sons born to Eleanor Matilda Slaughter and James Ossie Walton at Abington Memorial Hospital. When the twins reached age 2, the family moved from North Hills, Montgomery County, to Philadelphia.

Mr. Slaughter was a product of the city’s public schools. He attended Anna B. Pratt-Michael Arnold Elementary School, Gillespie Junior High School, and graduated in 1967 from Simon Gratz High School. He served as a teacher and principal for 33 years, including at Gillespie and Gratz.

He received a Philadelphia Board of Education scholarship and used it to earn a bachelor’s degree in secondary education from Cheyney University. Over the years, he received career certifications from Temple University, the University of Pennsylvania, St. Joseph’s University, La Salle University, and the Graduate School of Education at Harvard University.

In 1971, he began teaching social studies at Gillespie. He became social studies department chairman when his mentor, Dorothy M. Jenkins, retired.

In 1985, he transferred to Gratz, where he served as a social studies teacher and later the department head for social studies, world languages, and music. He was named assistant principal, and then principal.

Mr. Slaughter was assistant principal and principal at the William H. Shoemaker Junior High School in West Philadelphia before becoming principal of Bartram Human Services High School in 2000. It is now the Paul Robeson High School for Human Services.

When he first arrived, the human services school was an off-site annex of the larger Bartram High School. Under Mr. Slaughter’s leadership, the facility became a separate high school. His portrait hangs in the school’s auditorium. He retired in 2004.

Starting in 1973, Mr. Slaughter was a member of the Historic Jones Tabernacle A.M.E. Church. He served in numerous leadership roles.

His “greatest love and joy” was serving as a member of the Local Lay (laity) organization of the African Methodist Episcopal Church with outreach to the Episcopal District, his family said. He served as director of lay activities and, later, president of the Jones Tabernacle Local Lay.

“He was an encourager to everyone, even those who were physically unable to participate in this ministry,” his family said.

Mr. Slaughter was a member of Alpha Phi Alpha Fraternity Inc. through the R.H.O. Chapter, Philadelphia. He was elected the 11th president of the chapter in 1992 and served through 1997. He contributed so generously to the R.H.O. Education Foundation that a scholarship was created in his name.

Mr. Slaughter traced some of his family’s roots to Culpeper, Va., and in 2002 he met with many relatives from there. He spearheaded family reunions and was able to greet family from across the nation.

“It was like that final piece of the puzzle being put into place. He visited Culpeper so often they told him to register and vote there,” his family joked.

He also enjoyed music, reading, and fine dining with friends.

He is survived by his twin brother, John Melvin Slaughter; a sister, Dr. Sandra E. Wilson; and nieces and a nephew.

A viewing starting at 8:30 a.m. Monday, June 17, will be followed by an Alpha Phi Alpha Fraternity service at 10:15 and a funeral at 11 a.m., all at the Grace Baptist Church of Germantown, 25 W. Johnson St., Philadelphia. Burial will be in Ivy Hill Cemetery, Philadelphia.