Metro East school reports › St. Clair County › O Fallon Twp HSD 203
O'Fallon High School
O'Fallon High School is a public high school in O Fallon Twp HSD 203, serving grades 9 - 12 in O'Fallon, St. Clair County, Illinois. In the 2025 Illinois Report Card (2024-25 school year), the Illinois State Board of Education designated it Commendable.
State designation, last three report cards
- 2023Exemplary
- 2024Commendable
- 2025Commendable
What Commendable means: No student group performing at or below the level of the lowest 5 percent of schools, and overall performance outside the top 10 percent statewide.
How it compares with other St. Clair County high schools
| Measure | This school | County median | Diff. |
|---|---|---|---|
| ELA proficiency | 62.0% | 50.0%10 schools | +12.0 pts |
| Math proficiency | 52.9% | 30.6%9 schools | +22.3 pts |
| Chronic absenteeism | 21.3% | 38.0%12 schools | -16.7 pts |
| Average class size | 22.2 | 17.412 schools | +4.8 |
| Low-income enrollment | 28.0% | 56.5%12 schools | -28.5 pts |
Median of other high schools in St. Clair County with reported data, this school excluded, not weighted by enrollment. Proficiency is from the 2024-25 state tests. Illinois changed its proficiency cut scores in 2025, so these percentages cannot be compared with earlier years.
What stands out
- Math proficiency is 22.3 points above the median for other St. Clair County high schools (30.6%). A relative strength.
- Chronic absenteeism is 16.7 points below the median for other St. Clair County high schools (38.0%). A relative strength.
Before you buy for this school
- Confirm the attendance boundary for the exact address with O Fallon Twp HSD 203. Boundaries change, and a listing's school field is not a guarantee.
- Visit. A designation summarizes test results, growth and attendance. It does not describe a classroom.
- Read the full report card for student-group results, growth and staffing.
Thinking about living here? Read the O'Fallon area guide.
Looking for a home near O'Fallon High School?
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Other schools in O Fallon Twp HSD 203
- This is the only school in the district.
Sources
- Illinois Report Card: O'Fallon High School
- ISBE Report Card Public Data Sets, 2023, 2024 and 2025, retrieved 2026-10-06
- ISBE 2025 Report Card Glossary (designation definitions)
This page reports state-published data. It is not a rating or recommendation by Single Tree Team.
