Final answer:
Schoenberg's early work highlights include his avant-garde experiments with atonality and the creation of the twelve-tone scale, both of which subverted traditional Western musical expectations.
Step-by-step explanation:
The high point of Arnold Schoenberg's early works can be pinpointed to his experiments with atonality and the invention of the twelve-tone scale. Schoenberg's approach was radical as he defied the entire tradition of Western music, which since the Renaissance had been dominated by a set of scales that listeners had come to expect. His deliberate introduction of dissonance and unexpected notes subverted these expectations and marked a significant turning point in musical history. As an avant-garde composer, Schoenberg influenced many contemporary musicians and remains a key figure in the study of music theory and composition.