Glenwood High School is a public high school in Chatham, Illinois. It is the only high school of Ball Chatham Community Unit School District 5, which is in southern Sangamon County and includes Chatham, Glenarm, and the southern portion of Springfield, Illinois., Glenwood High School had 1,388 students and an average class size of 300.HistoryBall TownshipBall Township High School, sometimes called Ball Township Community High School, opened in September 1923 with 35 students; 2 seniors graduated at the end of the 1923 - 1924 school year. The school was established on New City Road, approximately four miles east of Chatham, three miles north and one mile east of Glenarm.There were numerous additions to the original school building, including the 1935 gymnasium.Ball Township graduated 21 seniors in May 1948, after which it picked up all the students from Chatham High School. The first combined Ball Township graduating class, under Ball Chatham Community Unit School District 5, was 34 seniors in May 1949.The last Ball Township High School graduating class was 1956, with 43 students; students moved to the first Glenwood High School when it opened in March 1957. Since then various combinations of grades have used the Ball Township site. The original 1924 section of the school was torn down in June 2013, but newer sections remain and continue to be used as Ball Elementary School.