Total enrollment
9,700
-65 (-1%) vs SY 2020-21
Williamson County
Illinois · Public K-12
Williamson County's school count of 26 reflects a public K-12 system serving about 9,700 students inside Illinois, around 15% of the county population. By grade band, the county runs 13 elementary, 5 middle, and 7 high schools.
4-year change in Williamson County
SY 2020-21 vs SY 2024-25School count
21
0 (0%) vs SY 2020-21
Source: NCES Common Core of Data, enrollment-weighted demographic averages
How Williamson County ranks
Among counties| Measure | This county | In Illinois | In the US |
|---|---|---|---|
| State test proficiency ranked highest first | 49.4% | #11 of 88 | N/A |
| Enrollment ranked largest first | 9,700 | #23 of 89 | #839 of 2,745 |
| Number of schools ranked most first | 21 | #33 of 89 | N/A |
| Students per teacher ranked fewest first | 13.7:1 | #63 of 89 | #1,227 of 2,655 |
| Free or reduced-price lunch share ranked highest first | 54.1% | #30 of 89 | #1,405 of 2,526 |
| Diversity index ranked most diverse first | 34.7% | #39 of 89 | #1,663 of 2,707 |
Counties need at least 3 schools and 1,000 students to be ranked. Test proficiency is ranked within the state only, since each state gives a different test. Each rank links to the full list.
Williamson County school rankings
Residents
66,876
all ages · ACS 5-yr
Schools
26
7 districts
Enrollment
9,700
students · NCES CCD
Median income
$65,604
Below Illinois avg
Free/reduced lunch
54.1%
Above Illinois avg
Elementary
13
4,418 students
Middle
5
2,395 students
High
7
2,887 students
Combined / other
1
schools
LARGEST DISTRICT
Marion CUSD 2
3,684 students · 7 districts in Williamson County
County vs. school enrollment demographics
Left bar is the racial makeup of Williamson County residents (Census ACS 5-year). Right bar is the enrollment-weighted makeup of public schools in the county (NCES CCD). NCES systematically under-reports Hispanic, Pacific Islander, and Native American enrollment for many schools; where the resident share is meaningful but the reported school share is zero, we mark the school bar "not reported".
County residents
School enrollment
Bachelor's+
26.2%
adults 25+
Poverty rate
9.7%
ACS 5-year
Unemployment
5.0%
civilian labor
Median age
42
21.3% under 18
Test scores in Williamson County
Latest 2024-25 ELA proficiency, 14 schools ranked. Illinois state average: 51.0%.
Top 5 schools (ELA)
- Adams School· 75.0%
- Carterville Intermediate Sch· 74.8%
- Washington Elem School· 70.7%
- Longfellow Elem School· 70.5%
- Tri-C Elementary School· 69.0%
Lowest 5 schools (ELA)
- Lincoln Elem School· 37.0%
- Washington Middle School· 38.0%
- Marion Jr High School· 43.8%
- Crab Orchard Elementary School· 57.2%
- Herrin C U S D 4 Elem School· 61.2%
| Name | City | Level | Grades | Enrollment | Rating |
|---|---|---|---|---|---|
| Marion High School | Marion | High | 09-12 | 1,075 | · |
| Marion Jr High School | Marion | Middle | 06-08 | 742 | · |
| Herrin C U S D 4 Elem School | Herrin | Elementary | 02-05 | 712 | · |
| Carterville High School | Carterville | High | 09-12 | 668 | · |
| Herrin High School | Herrin | High | 09-12 | 662 | · |
| Tri-C Elementary School | Carterville | Elementary | KG-03 | 650 | · |
| Herrin Middle School | Herrin | Middle | 06-08 | 513 | · |
| Carterville Intermediate Sch | Carterville | Middle | 04-06 | 500 | · |
| Lincoln Elem School | Marion | Elementary | KG-05 | 482 | · |
| Washington Elem School | Marion | Elementary | KG-05 | 465 | · |
| North Side Primary Center | Herrin | Elementary | PK-01 | 433 | · |
| Jefferson Elem School | Marion | Elementary | PK-05 | 376 | · |
| Carterville Jr High Sch | Carterville | Middle | 07-08 | 344 | · |
| Johnston City High School | Johnston City | High | 09-12 | 328 | · |
| Crab Orchard Elementary School | Marion | Elementary | PK-08 | 323 | · |
| Washington Middle School | Johnston City | Middle | 05-08 | 296 | · |
| Adams School | Creal Springs | Elementary | PK-08 | 283 | · |
| Jefferson Elem School | Johnston City | Elementary | PK-02 | 270 | · |
| Longfellow Elem School | Marion | Elementary | KG-05 | 261 | · |
| Lincoln Elem School | Pittsburg | Elementary | 03-04 | 163 | · |
| Crab Orchard High School | Marion | High | 09-12 | 154 | · |
| Project Echo | Johnston City | High | 07-12 | 0 | · |
| ROE 21 ALOP | Marion | Combined | 04-12 | 0 | · |
| ROE 21 Senior's Plus ALOP | Marion | High | 10-12 | 0 | · |
| Williamson Co Intensive Program | Marion | Elementary | M-M | · | · |
| Williamson Co Learning Cntr | Marion | Elementary | M-M | · | · |
Cities in Williamson County
About Williamson County
Williamson County is an average-sized Illinois county of about 66,876 residents, home to 26 public schools and roughly 9,700 students.
Stepping back, census numbers show the median household earns about $65,604 a year, 26% of adults hold a bachelor's degree or higher, and roughly 10% of residents live below the federal poverty line. That income level is 7% below the Illinois median.
On the school-mix side, Williamson County is made up of 13 elementary schools (4,418 students), 5 middle schools (2,395), 7 high schools (2,887), and 1 combined or other schools.
The largest single district in Williamson County is Marion CUSD 2, which alone enrolls about 3,684 students.
Over the past 4-year window. Combined enrollment now sits at 9,700 students, stayed largely flat from the 9,765 reported in SY 2020-21.
Within the allk12 community for this area, the community for Williamson County discusses comparison threads between local schools and program reviews. Posts come from current and former families, staff, and alumni.
Frequently asked questions
DATA · Census ACS 5-year · NCES Common Core of Data