Marlborough School, an independent, school serving young women in grades 7-12, announced on Wednesday that Dr. Priscilla G. Sands will become its ninth head of school, effective July 1.

Sands joins Marlborough from the Springside Chestnut Hill Academy in Philadelphia, where she has served as president since 2011.

She began her career teaching drama and English at her alma mater, Agnes Irwin School in Philadelphia, where she rose quickly through the ranks, overseeing the community service program, serving as director of admissions and financial aid and eventually being named assistant head of school. In 1996, Sands was tapped to lead Springside School, and in 2011, when Springside merged with the all-boys Chestnut Hill Academy, the new board appointed Sands president of the combined institution, Springside Chestnut Hill Academy.

“On behalf of the entire Marlborough Board of Trustees, I am delighted to welcome Dr. Sands and her family into our school community,” said board president Christine Ewell. “Her strong commitment to the education of girls, deep understanding of the changing landscape of 21st century education and thorough knowledge of the expectations of highly selective colleges and universities make Dr. Sands an ideal fit for Marlborough.”

During Sands’s 19-year tenure at Springside Chestnut Hill Academy, enrollment grew 63 percent; a fully transformed and unified campus was unveiled; extensive sustainability initiatives earned the school “Green Ribbon” status from the U.S. Department of Education; and, most recently, she established the Center for Entrepreneurial Leadership, a program that enhances the school’s core curriculum and has garnered national attention.

“I am honored and excited to have been chosen as the next leader of Marlborough,” Sands said. “As a strong believer in the power of all-girls education, I look forward to working with the talented and dedicated administration, faculty and staff to further the important mission of the school.”

Sands will replace Barbara Wagner, who will step down at the end of the academic year.