Complex sentence: At that time, Sun Shao Yun and three other local leaders created a school called "Chong Wen School" in Nanjing so that the children in the south of the Old City had a place to study.
Split into simpler sentences: At that time, Sun Shao Yun and three other local leaders created a school called "Chong Wen School" in Nanjing. Therefore, the children in the south of the Old City had a place to study.