Cornerstone Montessori Photo

Best Sumner Private Schools (2026)

For the 2026 school year, there is 1 private school serving 115 students in Sumner, WA (there are 10 public schools, serving 6,506 public students). 2% of all K-12 students in Sumner, WA are educated in private schools (compared to the WA state average of 10%).

Private Schools in Sumner, WA (2026)

School
Location
Quick Facts
Cornerstone Montessori
Cornerstone Montessori Photo
Montessori School
1644 Gault St
Sumner, WA 98390
(253) 987-7239
Gr: NS-6 | 115 students Avg. class size: 15 students Extracurrculars: 2 Tuition listed

Overview

This Town (Sumner)
This State (WA)
# Schools
1 School

Student Body:

# Students
115 Students
120,481 Students
% Average Students of Color
29%
31%

Academics and Faculty:

# Teachers
8 Teachers
9,954 Teachers
Average Student-Teacher Ratio
14:1
12:1
% Average Faculty w/Advanced Degree
30%
58%
Average Class Size
15 students
16 students

Tuition and Acceptance Rate:

Average Summer Program Cost
$990
$810

Students by Ethnicity:

0.22
0.64
# American Indian Students
n/a
1,235 Students
% American Indian Students
n/a
1%
# Asian Students
3 Students
9,056 Students
% Asian Students
2%
8%
# Hispanic Students
n/a
6,317 Students
% Hispanic Students
n/a
5%
# Black Students
1 Student
3,831 Students
% Black Students
1%
3%
# White Students
10 Students
59,335 Students
% White Students
9%
50%
# Hawaiian Students
n/a
658 Students
% Hawaiian Students
n/a
1%
# Two or more races Students
n/a
n/a
% of Two or more races Students
n/a
n/a
# Others Students
101 Students
38,553 Students
% of Others Students
88%
32%
All Ethnic Groups

Extracurriculars and Sports:

Average Number of Extracurriculars
2 extracurriculars
7 extracurriculars

Frequently Asked Questions

How many private schools are located in Sumner, WA?
1 private schools are located in Sumner, WA.
What percentage of students in Sumner go to private school?
2% of all K-12 students in Sumner are educated in private schools (compared to the WA state average of 10%).

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