Average
#278 of 381 private schools in WA
Cornerstone Montessori School
Elementary School
1644 GAULT ST, Sumner, WA 98390
Enrollment
38
Student-Teacher
7.6:1
Score
5.7
Grades
Pre-K – 6th
Enrollment
38
Student-Teacher
7.6:1
Score
5.7
Grades
Pre-K – 6th
Data vintage
2021-22
Data vintage2021-22
How this school compares
Washington private schools
#278 of 381
Shortlisting around Cornerstone Montessori School?
Use this profile as one decision point, then compare nearby options, source confidence, and commute fit before picking a neighborhood around it.
Shortlist starter
Start with these real page-level signals, then use the full table and map below.
Cornerstone Montessori School
Elementary School in Sumner · grades Pre-K – 6th. Start here, then compare fit against nearby and district options.
Maple Lawn Elementary
0.1 mi away. Use as a geographic alternative in the same move search.
Sumner Middle School
0.2 mi away. Use as a geographic alternative in the same move search.
About Cornerstone Montessori School
Cornerstone Montessori School is a private elementary school in Sumner, WA. Cornerstone Montessori School serves approximately 38 students, and covers grades Pre-K-6th, and has a 7.6:1 student-teacher ratio. Cornerstone Montessori School has a current MySchoolScout rating of 5.7 out of 10 and ranks #278 of 381 private schools in WA.
- This school 5.7 · Average
- WA avg 6.8
What Parents Should Know
At 38 students, Cornerstone Montessori School is on the smaller side. That usually buys more individual attention and teachers who know every kid by name, with the trade-off of fewer electives and extracurriculars than a larger school can staff. Ask what activities it actually offers.
At 7.6:1 students to teachers, Cornerstone Montessori School sits well below the national average. Smaller classes like that usually mean more one-on-one time between students and teachers.
Cornerstone Montessori School is private, so it runs independently of the local district and sets its own curriculum. That freedom cuts both ways depending on what you want for your child. If you're considering it, start with the practical questions: tuition, financial aid, and how admissions work.
Compare to Public Schools
BetaHow Cornerstone Montessori School compares to 5 public schools serving similar grades in Sumner, WA
Student Demographics
Nearby Elementary Schools
| School | Rating |
|---|---|
| Cornerstone Montessori School (this school) | 5.7 |
| Maple Lawn Elementary | 8.6 |
| Sumner Middle School | 7.8 |
| Sumner Special Services | — |
| Daffodil Valley Elementary | 6.8 |
| Liberty Ridge Elementary | 7.4 |
Demographics sourced from NCES Private School Survey (PSS) and Common Core of Data (CCD). Comparisons are based on enrollment-weighted averages.
Score Breakdown
PreliminaryWhat This Rating Measures
This rating reflects classroom size, instructional time, student diversity, community resources, and school characteristics. Private schools are ranked against other private schools in WA.
Data Unavailable
View data sources
Score basis: Private school model
Data coverage: 80% of scoring components had data
Components scored: 4 of 5
Ranking pool: Private schools in WA
Test Scores
Test score data not yet available for this school.
Student Demographics NCES PSS (SY 2021-22)
Source: NCES Private School Survey (PSS)
Location
1644 GAULT ST, Sumner, WA 98390
Nearby Alternatives
Families considering Cornerstone Montessori School may also want to explore other elementary schools in the area. Spinning Elementary (rated 9.2/10, 2.1 miles away, in nearby Puyallup), which scores notably higher. Another option is Maple Lawn Elementary (rated 8.6/10, 0.1 miles away), which scores notably higher. Additionally, Crestwood Elementary (rated 8.1/10, 2.4 miles away, in nearby Bonney Lake), which scores notably higher. For more schools in Sumner, see our Sumner schools guide .
Nearby Schools
20 within 2.6 mi| School | Distance | Rating |
|---|---|---|
| Maple Lawn Elementary Sumner | 0.1 mi | 8.6 |
| Sumner Middle School Sumner | 0.2 mi | 7.8 |
| Sumner High School Sumner | 0.7 mi | 7.4 |
| Sumner Special Services Sumner | 0.9 mi | — |
| Daffodil Valley Elementary Sumner | 1.1 mi | 6.8 |
| Shaw Road Elementary Puyallup | 1.4 mi | 6.8 |
| CASCADE CHRISTIAN SCHOOL - MCALDER ELEMENTARY Puyallup | 1.8 mi | 4.1 |
| NORTHWEST CHRISTIAN SCHOOL Puyallup | 1.4 mi | 6.3 |
| CASCADE CHRISTIAN -JUNIOR HIGH/HIGH SCHOOL Puyallup | 1.6 mi | 6.2 |
| Crestwood Elementary Bonney Lake | 2.4 mi | 8.1 |
| Spinning Elementary Puyallup | 2.1 mi | 9.2 |
| Lakeridge Middle School Bonney Lake | 2.2 mi | 7.4 |
| Wildwood Elementary Puyallup | 2.6 mi | 6.2 |
| Sunrise Elementary Puyallup | 3.0 mi | 5.9 |
| Ferrucci Jr High Puyallup | 2.9 mi | 5.7 |
| E B Walker High School Puyallup | 2.5 mi | 6.0 |
| Mt View Elementary Edgewood | 2.9 mi | 6.4 |
| CASCADE CHRISTIAN - PUYALLUP ELEMENTARY Puyallup | 2.6 mi | 4.3 |
| Kalles Junior High Puyallup | 2.6 mi | 5.5 |
| Stewart Elementary Puyallup | 2.6 mi | 4.8 |
Neighborhood Census ACS (2019-2023)
Census data for ZIP 98390 (ACS 2019-2023 5-Year Estimates) · Data sources
Median Income
$97,815
Median Home Value
$471,500
Median Rent
$1,886/mo
Population
11,497
College Educated
23%
Homeownership
51.3%
Avg Commute
30.2 min
Poverty Rate
6.9%
Median Age
35.9
Similar Schools
Schools in the same state with comparable level, size, and ratings
| School | Rating |
|---|---|
| Blaine Home Connection Blaine, WA | 5.7 |
| Orient Elementary School Orient, WA | 5.7 |
| COLVILLE VALLEY JUNIOR ACADEMY Colville, WA | 5.8 |
| CEDAR CREST ACADEMY KIRKLAND Kirkland, WA | 5.6 |
| FOREST PARK ADVENTIST CHRISTIAN SCHOOL Everett, WA | 5.6 |
| RIVERWOOD COMMUNITY SCHOOL Colville, WA | 5.6 |
Frequently Asked Questions
Common questions about Cornerstone Montessori School
What grades does Cornerstone Montessori School serve?
Cornerstone Montessori School serves students in grades Pre-K through 6th.
How many students attend Cornerstone Montessori School?
Cornerstone Montessori School has an enrollment of approximately 38 students.
What is the student-teacher ratio at Cornerstone Montessori School?
The student-teacher ratio at Cornerstone Montessori School is 7.6:1. A lower ratio generally means more individual attention per student. The national average is approximately 11:1 for private schools.
How does Cornerstone Montessori School rank in WA?
Cornerstone Montessori School ranks #278 of 381 private schools in WA.
What is Cornerstone Montessori School's MySchoolScout rating?
Cornerstone Montessori School has a current MySchoolScout rating of 5.7 out of 10. This score combines the level-appropriate components shown in the rating breakdown; equity data is shown separately for context.
Is Cornerstone Montessori School a private school?
Yes, Cornerstone Montessori School is a private coeducational school with a Nonsectarian affiliation. Private schools are not required to participate in state standardized testing, so academic performance data may be limited compared to public schools.
Is Cornerstone Montessori School a religious school?
No, Cornerstone Montessori School is a nonsectarian (non-religious) private school.
Explore More Schools
Neighborhood Context
Powered by 
Quick Facts NCES PSS (SY 2021-22)
- Grades
- Pre-K – 6th
- Enrollment
- 38
- Gender Split
- 55% M / 45% F
- Student-Teacher Ratio
- 7.6:1
- Teachers (FTE)
- 5
- Type
- private
- Coed Status
- coed
- Affiliation
- Nonsectarian
- School Day
- 6 hours
- Days Per Year
- 190 days
- Setting
- Large Suburb
- County
- Pierce County
- Phone
- (253) 987-7239
Resources & Links
How we rate schools
A clear 1–10 score built from public data — growth, academics, and learning environment. No hidden criteria, no pay-to-play.
See how we rateRelated reading
Get school insights in your inbox
New rankings, best-schools lists, and parent guides — delivered free. No spam, unsubscribe anytime.
We respect your privacy. Unsubscribe at any time.