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 approximately 6,750 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.
Beginning in 1884, a single public school, Union School, taught all Crystal Lake elementary and high school students. In 1907, the high school moves into its own building on the Union School grounds. Twelve years later, Community High School District 155 is established by a ballot measure in December of 1919. H.A. Dean served as the district's first superintendent. Crystal Lake Community High School opens at the current site of Crystal Lake Central High School on May 12, 1924. The school serves students from Crystal Lake, Cary, Fox River Grove, and the surroundin areas, all of whom attended Crystal Lake Community High School until 1961, when Cary-Grove High School was opened. Crystal Lake South High School opened in 1978. At that time, Crystal Lake Community High School became Crystal Lake Central. A fourth high school, Prairie Ridge, opened in 1997. The district opened an alternative education campus, Haber Oaks Campus, in 2008.
Students come to the high schools from several public school feeder districts including Crystal Lake District 47, Cary Community Consolidated School District 26, Fox River Grove School District 3, and Prairie Grove School District 46.
All District 155 juniors take the American College Test (ACT) as part of the Prairie State Achievement Exam. The composite score for Community High School District 155 seniors graduating in 2012 is 22.5 compared to a state average of 20.3. In other testing, the district is one of only 539 districts in the U.S. and Canada named to the 2012 AP District Honor Roll by the College Board for increasing AP participation while maintaining student success rates. In 2013, the district’s students took 1,876 Advanced Placement exams in subjects including biology, calculus, chemistry, computer science, drawing, English language & composition, English literature & composition, European history, French, German, physics, psychology, music theory, U.S. history, Spanish, statistics, studio art 2D, studio art 3D. Honor scores (three or higher) were received on 85% of these examinations. Further, 91.2% of the students in the class of 2013 continued their education beyond high school at 2- or 4-year colleges/universities or technical/vocational schools.
Each year the Chicago Sun-Times ranks Illinois' 689 high schools. All four District 155 schools are in the top 25% of all public high schools. This includes Cary-Grove (54th, 7.8%), Prairie Ridge (60th, 8.7%), Crystal Lake Central (157th, 22.8%), and Crystal Lake South (90th, 13.1%). Further, Newsweek/The Daily Beast lists Cary-Grove and Prairie Ridge in the top 3% of all U.S. public high schools. Cary-Grove ranked 733rd in the country (32nd in Illinois) for the 2013 ranking while Prairie Ridge ranked 767th in the country and 34th in Illinois. Additionally, the U.S. News & World Report ranked Cary-Grove as the 1,414th best public high school in the country for 2013.
The district employs nearly 700 people including approximately 400 teachers, sixteen building administrators, and a full complement of district administrators, guidance 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 85% hold master's degrees or higher.
District 155 is one of Illinois' most financially healthy school districts, having received the highest financial rating from the Illinois State Board of Education for each of the last ten school years. The Financial Recognition rating is based on fund balance to revenue ratio, expenditures to revenue ratio, days cash on hand, short-term borrowing, and long-term debt.
Dr. Johnnie Thomas is the district's eleventh superintendent, succeeding Dr. Jill Hawk in 2012.