Private school · Mercer Island, King County · grades PK, K-12 · Roman Catholic
Snapshot
K-12 enrollment
229
SBE-reported, 2024-25
Student-teacher ratio
12.1:1
NCES PSS, 2021-22
Teachers (FTE)
17
NCES PSS, 2021-22
Identity and approval
Campus
St Monica Catholic School — 4320 87th Ave SE, Mercer Island 98040
Host public district
Mercer Island School District
Grades
PK, K-12
Religious affiliation
Roman Catholic
WA SBE approval
2026-27 (state-approved private school)
Profit status
Nonprofit
Enrollment
K
1
2
3
4
5
6
7
8
9
10
11
12
22
20
20
23
26
25
28
25
21
7
5
5
2
Enrollment by grade, 2024-25 school year, as reported to the WA State Board of Education.
Academics
Washington private schools are not required to publish state assessment results. No public score data exists for this school.
Student demographics
Asian
8%
Black
2%
Hispanic
5%
White
71%
NCES Private School Universe Survey, 2021-22 (the most recent federal collection). Private-school demographics are reported biennially and lag public-school data.
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