Enrollment
1,443
Illinois · 2024-25 NCES data
High school (grades 9-12) · Crystal Lake, IL
Federal NCES profile for Crystal Lake Central High School, including enrollment, faculty, free-lunch eligibility, demographics, and resource indicators - Resource Investment Index 47/100.
The verdict
Crystal Lake Central High School earns 47/100 on the Resource Investment Index, with class sizes larger than 84% of Illinois schools. It is also one of the largest schools in Illinois.
Crystal Lake Central High School has class sizes larger than 84% of Illinois schools. Computed live against every Illinois school reporting to NCES.
By Resource Investment Index, Crystal Lake Central High School ranks #3 of 3 high schools in Crystal Lake, IL.
NCES ID 171137001367 Verify on NCES CCD record →
Enrollment
1,443
Illinois · 2024-25 NCES data
Teachers (FTE)
87.0
Federal CCD staff survey
Students per teacher
16.6:1
vs 14:1 Illinois avg
+19% vs state
How Crystal Lake Central High School compares with Illinois and U.S. medians
Slightly above state median
16.6:1 - 2.6 above the Illinois state median of 14:1, indicating larger average class loads than typical schools in the state.
Crystal Lake Central High School is a large high school in Crystal Lake, Illinois, enrolling 1,443 students.
Class loads run somewhat heavier than typical: 16.6:1 puts it in the larger third of Illinois schools by student-teacher ratio.
By headcount it is one of the larger campuses in Illinois, bigger than 96% of state schools at 1,443 students.
Its Resource Investment Index lands in the lower third of 3,845 scored Illinois schools.
Its student body is led by White (64%) and Hispanic or Latino (28%) (diversity index 51/100).
On the academic-pipeline side it reports 20 Advanced Placement courses.
Counselor coverage runs a bit thin, about 289 students per counselor, somewhat past the ASCA-recommended 250:1 benchmark.
Chronic absenteeism is elevated: 28.1% of students missed 10% or more of school days (2021-22 Civil Rights Data Collection).
The surrounding Chsd 155 spends $22,088 per pupil, 30% above the Illinois average, a better-resourced district than most.
Among Crystal Lake's high schools, it stands alongside Crystal Lake South High School (1,279 students): Crystal Lake Central High School is larger than that campus by headcount and runs leaner classes (16.6:1 vs 17.5:1).
Chsd 155 also operates Cary-Grove Community High School (1,348 students) and Crystal Lake South High School (1,279 students) alongside Crystal Lake Central High School.
Sourced from NCES CCD, CRDC, and F-33 (federal records, not a quality verdict). How we source and compute this.
Source: National Center for Education Statistics Common Core of Data + CRDC + F-33 · 2024-25
Crystal Lake Central High School on the metrics families compare, against Illinois and U.S. means.
| Metric | This school | vs Illinois | Illinois avg | U.S. avg |
|---|---|---|---|---|
| Students per teacher | 16.6:1 | ▲ 19% | 14:1 | 15.7:1 |
| Enrollment | 1,443 | top 4% | - | - |
Source: NCES Common Core of Data School-level CCD + state/national means from Public School Universe · 2024-25
Three separate federal collections, each on its own reporting cadence - which is why this school's numbers line up on a consistent basis against every other school and state on this site, rather than mixing figures pulled from different survey years.
Largest group: White at 64.2% of enrollment.
Simpson diversity index - at 50.8, Crystal Lake Central High School is more mixed than the Illinois school average of 38.9.
District-wide per-pupil expenditure for Chsd 155, which includes Crystal Lake Central High School.
Source: NCES F-33 School District Finance Survey District-level finance · FY 2021-22 Per-pupil expenditure reflects the district-wide average. Individual school budgets are not reported at the federal level.
| School | Enrollment | Economic Profile | Student-Teacher Ratio |
|---|---|---|---|
| Cary-Grove Community High School | Similar size | No free-lunch data | Similar S:T ratio |
| Crystal Lake South High School | Similar size | No free-lunch data | Similar S:T ratio |
| Prairie Ridge High School | Similar size | No free-lunch data | Similar S:T ratio |
Comparisons are relative to Crystal Lake Central High School's own figures; each column derives from NCES Common Core of Data.
2 comparable high schools (grades 9-12) serving the same city.
Matched by enrollment size and by staffing ratio across all of Illinois, not just this city - a different peer set than the local comparisons above.
Next steps
Verify locally before acting on Crystal Lake Central High School's federal record.
Federal record (CCD 2024-25, CRDC 2021-22) - PlainSchools assigns no subjective rating; the composite quality score is a transparent, reproducible index computed from this cited federal data.
Crystal Lake Central High School has 1,443 students enrolled. It is a high school in Crystal Lake, IL.
The student-teacher ratio at Crystal Lake Central High School is 16.6:1, which is 19% higher than the Illinois average of 14:1 and 6% higher than the national average of 15.7:1.
The largest demographic group at Crystal Lake Central High School is White at 64.2% of enrollment, in Crystal Lake, IL. Its student body is more racially and ethnically mixed than most US schools, with a diversity index of 50.8/100.
Crystal Lake Central High School has a Resource Investment Index of 47/100 (typical reported resources relative to schools nationally) based on 5 factors: student-teacher ratio, AP course offerings, counselor availability, attendance rates. Not a test-score or academic measure (national median ~41/100, see methodology).
By Resource Investment Index, Crystal Lake Central High School ranks #3 of 3 high schools in Crystal Lake, IL. This compares federal resource and staffing data among local peers; it is not a test-score or academic ranking. See all high schools in Crystal Lake on the city page.
Crystal Lake Central High School earns 47/100 on the Resource Investment Index, with class sizes larger than 84% of Illinois schools. It is also one of the largest schools in Illinois. This is a resource snapshot, not an academic rating; see the Resource Investment Index question above for what the number does and doesn't measure.
Besides Crystal Lake Central High School, Chsd 155 also operates Cary-Grove Community High School (1,348 students), Crystal Lake South High School (1,279 students), and Prairie Ridge High School (1,133 students). See the Chsd 155 district page for the complete list.
Every figure on PlainSchools is rendered directly from the source NCES, CRDC and F-33 federal records, no number is typed in by an editor. Each school's figures reflect its most recent NCES/CRDC submission on file. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of June 2026.
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PlainSchools, “Crystal Lake Central High School, Crystal Lake IL.” Compiled from NCES Common Core of Data, Civil Rights Data Collection, and the NCES F-33 finance survey; data as of June 2026. https://plainschools.com/schools/crystal-lake-central-high-school-il
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