Complex sentence: The first students in the town of Buckeye graduated in 1921, and regular graduating classes began the next year for what was then known as Buckeye High School, and there were 23 alumni by 1925.
Split into simpler sentences: The first students in the town of Buckeye graduated in 1921. Regular graduating classes began the next year for what was then known as Buckeye High School, and there were 23 alumni by 1925.