Final answer:
The Octagon Earthwork in Newark, Ohio is used for educational and cultural purposes, serving as a monument to the Hopewell culture's astronomical knowledge and organizational skills. It reflects a broader trend of repurposing historical sites for environmental theatre and other modern uses.
Step-by-step explanation:
The current use of the Octagon Earthwork in Newark, Ohio is primarily for educational and cultural purposes. These ancient structures, created by the Hopewell culture, were originally designed to align with the moon's movement and were likely used for predicting lunar eclipses and seasonal events. Today, this site serves as a historical monument where visitors can learn about the advanced astronomical knowledge and organizational skills of the Hopewell people. Additionally, similar abandoned spaces have been repurposed for environmental theatre, indicating a modern utilization of old structures and spaces for artistic performances, which reflects a broader trend in urban repurposing.