Average
#728 of 992 private schools in NY
St Mary School
Elementary School
16 HARRISON AVE, East Islip, NY 11730
Enrollment
351
Student-Teacher
13.2:1
Score
5.6
Grades
Pre-K – 8th
Enrollment
351
Student-Teacher
13.2:1
Score
5.6
Grades
Pre-K – 8th
Data vintage
2021-22
Data vintage2021-22
How this school compares
New York private schools
#728 of 992
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St Mary School
Elementary School in East Islip · grades Pre-K – 8th. Start here, then compare fit against nearby and district options.
John F Kennedy Elementary School
0.6 mi away. Use as a geographic alternative in the same move search.
Wing Elementary School
1.1 mi away. Use as a geographic alternative in the same move search.
About St Mary School
St Mary School is a private elementary school in East Islip, NY. St Mary School serves approximately 351 students, and covers grades Pre-K-8th, and has a 13.2:1 student-teacher ratio. St Mary School has a current MySchoolScout rating of 5.6 out of 10 and ranks #728 of 992 private schools in NY.
- This school 5.6 · Average
- NY avg 5.9
What Parents Should Know
St Mary 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 St Mary School compares to the 2 public schools in East Islip, NY
Student Demographics
All Schools in East Islip
| School | Rating |
|---|---|
| St Mary School (this school) | 5.6 |
| JOHN F KENNEDY ELEMENTARY SCHOOL | 6.1 |
| TIMBER POINT ELEMENTARY SCHOOL | 4.5 |
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 NY.
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 NY
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
16 HARRISON AVE, East Islip, NY 11730
Nearby Alternatives
Families considering St Mary School may also want to explore other elementary schools in the area. IDLE HOUR ELEMENTARY SCHOOL (rated 8.3/10, 2.3 miles away, in nearby Oakdale), which scores notably higher. Another option is WING ELEMENTARY SCHOOL (rated 7.5/10, 1.1 miles away, in nearby Islip), which scores notably higher. Additionally, FRANCIS J O'NEILL SCHOOL (rated 6.7/10, 3.5 miles away, in nearby Central Islip), which scores notably higher. For more schools in East Islip, see our East Islip schools guide .
Nearby Schools
20 within 4.0 miNeighborhood Census ACS (2019-2023)
Census data for ZIP 11730 (ACS 2019-2023 5-Year Estimates) · Data sources
Median Income
$146,190
Median Home Value
$577,600
Median Rent
$2,508/mo
Population
14,376
College Educated
38.9%
Homeownership
85%
Avg Commute
30.7 min
Poverty Rate
4.5%
Median Age
41.5
Similar Schools
Schools in the same state with comparable level, size, and ratings
| School | Rating |
|---|---|
| ALICE E GRADY ELEMENTARY SCHOOL Elmsford, NY | 5.6 |
| BEMUS POINT ELEMENTARY SCHOOL Bemus Point, NY | 5.6 |
| BNEI YAKOV YOSEF OF MONSEY Spring Valley, NY | 5.6 |
| C R WEEKS ELEMENTARY SCHOOL Windsor, NY | 5.6 |
| CENTENNIAL AVENUE ELEMENTARY SCHOOL Roosevelt, NY | 5.6 |
| CRAIG ELEMENTARY SCHOOL Schenectady, NY | 5.6 |
Frequently Asked Questions
Common questions about St Mary School
What grades does St Mary School serve?
St Mary School serves students in grades Pre-K through 8th.
How many students attend St Mary School?
St Mary School has an enrollment of approximately 351 students.
What is the student-teacher ratio at St Mary School?
The student-teacher ratio at St Mary School is 13.2:1. A lower ratio generally means more individual attention per student. The national average is approximately 11:1 for private schools.
How does St Mary School rank in NY?
St Mary School ranks #728 of 992 private schools in NY.
What is St Mary School's MySchoolScout rating?
St Mary School has a current MySchoolScout rating of 5.6 out of 10. This score combines the level-appropriate components shown in the rating breakdown; equity data is shown separately for context.
Is St Mary School a private school?
Yes, St Mary School is a private coeducational school with a Roman Catholic affiliation. Private schools are not required to participate in state standardized testing, so academic performance data may be limited compared to public schools.
Is St Mary School a religious school?
St Mary School has a Roman Catholic religious affiliation.
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Neighborhood Context
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Quick Facts NCES PSS (SY 2021-22)
- Grades
- Pre-K – 8th
- Enrollment
- 351
- Gender Split
- 51% M / 49% F
- Student-Teacher Ratio
- 13.2:1
- Teachers (FTE)
- 27
- Type
- private
- Coed Status
- coed
- Affiliation
- Roman Catholic
- School Day
- 6 hours
- Days Per Year
- 180 days
- Setting
- Large Suburb
- County
- Suffolk County
- Phone
- (631) 581-3423
Resources & Links
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