For the 2026 school year, there is 1 private high school serving 383 students in Clinton County, IL.
The top-ranked private high school in Clinton County, IL is Mater Dei High School.
100% of private high schools in Clinton County, IL are religiously affiliated (most commonly Catholic).
Top-Ranked Clinton County Private High Schools (2026)
School
Location
Quick Facts
Mater Dei High School
(Catholic)
900 Mater Dei Dr
Breese, IL 62230
(618) 526-7216
Breese, IL 62230
(618) 526-7216
Gr: 9-12 | 383 students Avg. class size: 16 students Sports: 12 Tuition listed
Overview
This County (Clinton County)
This State (IL)
# Schools
1 School
Student Body:
# Students
383 Students
89,879 Students
% Average Students of Color
5%
35%
Academics and Faculty:
# Teachers
30 Teachers
7,553 Teachers
Average Student-Teacher Ratio
13:1
11:1
% Average Faculty w/Advanced Degree
50%
56%
Average Class Size
16 students
15 students
Average Number of AP Courses
2 courses
11 courses
Average ACT score
24
(Out of 36)
25
Tuition and Acceptance Rate:
Average Yearly Tuition Cost
$6,310
$15,778
Students by Ethnicity:
Diversity Score
0.14
0.62
# American Indian Students
n/a
298 Students
% American Indian Students
n/a
n/a
# Asian Students
2 Students
5,624 Students
% Asian Students
n/a
6%
# Hispanic Students
16 Students
10,091 Students
% Hispanic Students
4%
11%
# Black Students
n/a
9,671 Students
% Black Students
n/a
11%
# White Students
355 Students
52,469 Students
% White Students
93%
58%
# Hawaiian Students
n/a
105 Students
% Hawaiian Students
n/a
n/a
# Two or more races Students
n/a
n/a
% of Two or more races Students
n/a
n/a
# Others Students
10 Students
12,146 Students
% of Others Students
3%
14%
All Ethnic Groups
Extracurriculars and Sports:
Average Number of Sports
12 sports
9 sports
Frequently Asked Questions
What are the top-ranked private high schools in Clinton County, IL?
The top-ranked private high schools in Clinton County, IL is Mater Dei High School.
How many private high schools are located in Clinton County?
1 private high schools are located in Clinton County.
What percentage of private high schools are religiously affiliated in Clinton County?
100% of private high schools in Clinton County are religiously affiliated (most commonly Catholic).
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