Crystal Lake South High School: Top Public High School in Crystal Lake IL (2026 List)

About Crystal Lake South High School

Top rated public high school in CRYSTAL LAKE, IL, Crystal Lake South High School has 1,507 students and is ranked 214th in the National Rankings. It is one of four high schools in Community High School District 155, with an approximate enrollment of 1,291 students and an approximate student-to-teacher ratio of 17:1. The school is famous for its academic rigor and has the best comprehensive Advanced Placement (AP) programs and exams with 44% AP participation rate.The student body at Crystal Lake South High School is diverse, with 32% of the total enrollment being minority students. The school is a leading school supporting all learners, including those from economically disadvantaged backgrounds, with extensive resources and SAT prep. The latest academic data indicates: 26% proficiency in Mathematics 34% proficiency in Reading The school has a per-pupil expenditure of $19,000+, making it a well-resourced environment for growth. It is one of the most popular schools to promote a community-centric and a supportive learning environment overall, and it is one of the best high schools in Illinois.

Academic Performance

Subject Proficiency

Mathematics 26%

Reading 34%

State average proficiency is 26% in Math and 34% in Reading.

75

Full-time Teachers

17 : 1

Student-Teacher Ratio

1291

Total Students

$66456

Avg. Teacher Salary

Student Demographics

White 68.09%

Asian 3.8%

Hispanic 24.09%

Black 2.87%

Two+ Races 0.85%

Native Am. 0.31%

White

68.09%

Asian

3.8%

Hispanic

24.09%

Black

2.87%

Two+ Races

0.85%

Native Am.

0.31%

Gender Distribution

Total Students: 1291

49.26%

636 Female

50.74%

655 Male

Student Population

1291 Students

With a student-teacher ratio of 17 : 1

Minority Enrollment

25%

Percentage of minority students

Students per Counselor

258 : 1

Student to counselor ratio

Crystal Lake South High School Contact Information

Address

1200 S McHenry Ave, Crystal Lake, IL, 60014

View on Map

Phone

(815) 455-3860

Call Now

Website

http://ww2.d155.org/cls/default.aspx

Recent News & Updates

New Playground Name

We are so excited to announce the name of our new playground! Following a school-wide and Robinson community vote we narrowed a large list of names down to four. Since our students will be using the playground on a daily basis, we gave them the final vote! 476.....

School Timings

Regular School Hours

All Grades: 7:25 AM to 2:50 PM

Early Dismissal Days

Dismissal Time: 12:15 PM

Note: Doors open at 7:10 AM for student arrival. Please refer to the school calendar for specific early dismissal dates.

After School Activities

Information coming soon

School Session Dates

September to June

School session starts in September 1st week and ends in June 3rd week. For exact dates, please contact the school.

Remarkable Alumni

Being Updated

Map

Latest News

Crystal Lake South High School’s Board approved Dan DeBruycker as the next principal beginning July 1, 2026, following his tenure as principal at Metea Valley High School and earlier roles at CLS as math teacher and coach. Theatre director Ben Stoner won the Illinois Theatre Association’s 2025 Award of Excellence in Secondary Education and was nominated for Best Direction for The SpongeBob Musical from the Illinois High School Musical Theatre Awards. Crystal Lake South was also named one of only 21 schools nationwide to receive the Disney on Broadway School of Excellence distinction, providing free licensing and resources to produce a Disney musical in 2025-2026.

FAQ

Q1. Does Crystal Lake South High School support learning through practical activities?

Ans. Yes, students work on projects and do things that help them learn skills they can use in the real world.

Q2. What does Crystal Lake South High School do to make the learning environment better?

Ans. Respect, working together, and being responsible make sure that the school culture is safe, welcoming, and open to everyone.

Q3. Does Crystal Lake South High School help students think of new things?

Ans. Yes, students can find out more about art, music, and new projects that will help them be more creative.

Q4. Are college entrance exams conducted here?

Ans. Students can take the SAT and ACT tests on-site or through programs that work together.

Q5. What does Crystal Lake South High School teach?

Ans. Crystal Lake South High School has a college-preparatory curriculum and gives students chances to learn through practical activities and improve their skills.

Games & Extracurricular Activities

Sports

Soccer Club Grades 1-3 | Mon/Wed 3:30-4:30pm
Basketball Grades 2-4 | Tue/Thu 3:30-4:45pm
Track & Field Grades 3-5 | Fri 3:30-5:00pm

Arts

Art Club Grades K-2 | Mon 3:00-4:00pm
Drama Club Grades 3-5 | Wed 3:30-5:00pm
Choir Grades 2-5 | Thu 3:15-4:15pm

Clubs

Chess Club Grades 2-5 | Fri 3:15-4:15pm
Garden Club All Grades | Tue 3:15-4:00pm
Robotics Club Grades 3-5 | Thu 3:30-5:00pm

Note: Schedules may change during school holidays. Please contact School for exact Schedule.

Summer Suggested Reading

Horn Book Selections

Vocabulary.com +3 Horn Book +3 What to Read to Your Kids +3

ML

Maggie Lou, Firefox

by Arnolda Dufour Bowes

PS

The Puppets of Spelhorst

by Kate DiCamillo

MLV

The Mona Lisa Vanishes

by Nicholas Day

Vocabulary.com Top Picks

Penguin Random House +10 Vocabulary.com +10 Wikipedia +10

F

Frindle

by Andrew Clements

WR

The Wild Robot

by Peter Brown

JGP

James and the Giant Peach

by Roald Dahl

Penguin Random House Features

Horn Book +2 Penguin Random House +2 The Guardian +2

SLB

The Secret Language of Birds

by Lynne Kelly

S

The Swifts: A Dictionary of Scoundrels

by Beth Lincoln

Free Robotics and Stem In-person Workshop in Your Neighbourhood for 7-14 Years Tech Enthusiasts.

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What Parents Say