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Crystal Lake South High School
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Opened in 1978, Crystal Lake South High School offers students a comprehensive 9-12 grade education including more than 200 courses. These include specialized Advanced Placement, dual credit, Project Lead the Way (PLTW), and Virtual Enterprises International (VEI) course offerings. The school is consistently ranked among the best public high schools in Illinois. In fact, in its most recent annual ranking of all 677 Illinois public high schools, the Chicago Sun-Times listed Crystal Lake South as the 114th best school in the state. Crystal Lake South High School is nationally recognized, most recently being named to the Washington Post's 2017 list of America's Most Challenging High Schools.  

Along with the other District 155 schools, Crystal Lake South appeared on the College Board's 2017 AP District Honor Roll for the sixth consecutive year. The honor roll recognizes districts that increased AP participation while maintaining student success rates on the exams. Only 447 districts in the United States and Canada appeared on the 2017 honor roll.

In athletics, the Crystal Lake South Gators compete in the Valley Division of the Fox Valley Conference. Including a fourth place finish in 2013, the school has finished in the state's top four in girls' volleyball five times dating back to 1991. In boys' golf, the school captured the state title in 1980, and took third in both 1981 and 1998. On the diamond, the baseball team won the IHSA Class 4A state championship title in 2017. Former professional baseball pitcher, Scott Olsen, is a 2002 graduate of Crystal Lake South.

The school offers students 34 clubs and activities. These activities include several opportunities to participate in community service, the arts, music, and other specialized interests. CLS alumni include TV writer Tom Mularz, brothers Nick (actor) and Matt (chef) Eversman, and season 1 American Idol finalist Jim Varraros.

Crystal Lake South has 90 teachers, all instructing in his or her academic ma­jor. In fact, 85% hold a master's degree or higher. The school also employs five counselors, two social workers, and one psychologist on its student services team.

Located approximately 45 miles north­west of Chicago, the school serves Crystal Lake and Lake in the Hills. The school is led by Josh Nobilio, who became principal in 2017.



Enrollment & Staffing

Crystal Lake South: 1,448

District 155: 6,395

District 155 Average Class Size: 20

Teachers with a Master's Degree or Higher: 85%

Continuing Education

Students Continuing Their Education After High School: 91%

            4-Year University/College: 62%

            Two-Year Community College: 26%

               Technical/Vocational School: 3%

4-Year Graduation Rate

Crystal Lake South: 98%

District 155: 97%

State: 87%

2018 SAT Composite

Crystal Lake South: 1105

District 155: 1102

State: 1018

2017 Advanced Placement

Exams Taken

Crystal Lake South: 907

District 155: 3,559

Percentage of Exams Earning Honor Scores

Crystal Lake South: 80%

District 155: 80​

Fight Song Lyrics:
Cheer for the fighting Gators!
There are no imitators.
Green and the Gold prevail,
South High School hail, Ra Ra Ra!
Fight Gators fight with might.
Win Gators, win tonight.
South High with Green and Gold has victory tonight!

District 155's Mission Statement:
For each student, we will inspire a love for learning, empower the pursuit of personal aspirations, and nurture the desire to contribute to the world.

                                                                                                                                                                       (Updated 10/17/17)

Crystal Lake South
High School
1200 South McHenry Avenue
Crystal Lake, IL 60014
Phone: 815-455-3860
Home of the Gators