Crystal Lake Central High School, often referred to as "Central" or "CLC," is the oldest of the three high schools in Crystal Lake, Illinois, United States.

Another addition was completed to the west-end of the building in the 1964–1965 school year.

Crystal Lake Community (and Union School before it) served students in grades 9–12 from Crystal Lake, Cary, and the surrounding areas of McHenry County.

[6] Since then, Central's student-athletes have won Illinois High School Association state titles in boys track and field, boys baseball, girls track and field, wrestling, girls tennis (mid 1970s), and girls cross country.

Notable team finishes at the Illinois state level include:[7]