Complex sentence: She studied at the Hollywood Professional School, a K-12 school for working professional children run by Maurice and Bertha Mann, where classes typically ran from 8:45 AM to 12:45 PM, allowing the students the afternoon off to pursue various jobs or performing careers.
Split into simpler sentences: She studied at the Hollywood Professional School, a K-12 school for working professional children run by Maurice and Bertha Mann. At HPS, classes typically ran from 8:45 AM to 12:45 PM, allowing the students the afternoon off to pursue various jobs or performing careers.