Complex sentence: Castilleja was founded in 1907 by Mary Ishbel Lockey, who was encouraged by Stanford University's first President-David Starr Jordan-to start a school that would offer girls a comprehensive, college preparatory education.
Split into simpler sentences: Castilleja was founded in 1907 by Mary Ishbel Lockey. She was encouraged by Stanford's first President, David Starr Jordan, to start a school that would offer girls a comprehensive, college preparatory education.