Crystal Lake South High School Community High School District 155 includes four comprehensive high schools and one alternate education campus. Serving grades 9-12, each institution has full State of Illinois recognition and accreditation. Enrollment includes 6,113 students from Bull Valley, Burton's Bridge, Cary, Crystal Lake, Fox River Grove, Lake in the Hills, Lakewood, Oakwood Hills, Prairie Grove, and Ridgefield. The district covers 67.75 square miles and is located approximately 45 miles northwest of Chicago in McHenry and Lake counties.
In 2017, The Washington Post honored District 155 for maintaining a high level of rigor in its schools. Cary-Grove (1,149), Crystal Lake South (1,345), and Prairie Ridge (1,254) all ranked among the top nationally. The Washington Post's national list includes about 22,000 with three District 155 schools ranking in the top 2,000. Further, Newsweek lists Cary-Grove and Crystal Lake Central in the top 3% of all U.S. public high schools.
The district employs nearly 741 people including teachers, building administrators, and a full complement of district administrators, school counselors, social workers, school psychologists, school nurses, support staff, and special education services personnel. In the core subjects, all of the district's teachers are teaching in their academic major. In fact, approximately 86% hold master's degrees or higher.