Excellent
#160 of 990 schools in CT
Top 16% in state
Cos Cob School
Elementary School · Greenwich School District · Cos Cob, CT
A Greenwich School District elementary school where students score 4 points below what's typical for similar communities.
300 East Putnam Ave., Cos Cob, CT 06807
- Math 62% proficient (2022)
- Reading 67% proficient (2022)
- 9.7:1 student-teacher ratio
Academics
Full Profile · 3/3 metricsView breakdown
View breakdown
View breakdown
Students at Cos Cob School score 64% proficient, which is below what's typical for similar communities (expected: 69%).
2022 EdFacts proficiency
Most recent published year. School vs. CT average.
Trend
↓ DecliningProficiency has fallen 9 points since 2019, to 65% in 2022, across a 14-year record (2009–2022).
Show all 13 years
Multi-year averages used by the rating model: math 73% (multi-year average, 2009-2022) · reading/ELA 74% (multi-year average, 2009-2022)
* COVID-affected year — test participation was uneven nationwide. This data is weighted at 50% in the Growth score calculation.
Based on 26 test records from CT state assessments and EdFacts (NCES).
Equity & diversity
Shown separately, not included in the overall scoreFree/reduced lunch
14.1%
Students qualifying for federal meal assistance
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 rateThe neighborhood
Where Cos Cob School sits, and what the surrounding area looks like.
Nearby same-level schools are colored by their score. Pins are locations, not attendance boundaries.
Getting around & local context
- Walk 83Very Walkable
- Bike 60Bikeable
Powered by
Area profileU.S. Census ACS 5-year estimates (ACS 2019–2023 5-year estimates)
Median income
$194,492
Median home value
$1,228,000
Median rent
$2,622/mo
College educated
72.9%
Homeownership
67.9%
Poverty rate
5.6%
ACS 2019–2023 5-year estimates for the ZCTA associated with school ZIP 06807; this is area context, not an attendance boundary.
Programs & students
Programs & Offerings
Compare nearby
Nearby same-level schools
4 from a 5-mile search; district fallback available
| School | Score | Grades | Distance | Enrollment | Compare |
|---|---|---|---|---|---|
| The Greenwich Country Day SchoolPrivate · tuition | 5.8private | PK–12 | 1.0 mi | 1,254 | Compare → |
| Riverside SchoolEnrollment path unverified | 9.7 | K–5 | 1.1 mi | 473 | Compare → |
| Julian Curtiss SchoolEnrollment path unverified | 7.8 | PK–5 | 1.2 mi | 246 | Compare → |
| International School at DundeeEnrollment path unverified | 9.7 | K–5 | 1.4 mi | 325 | Compare → |
Distance is proximity only; it is not attendance eligibility.
Private · tuition: Potential private option; tuition and admission requirements have not been verified.
Enrollment path unverified: Potential public school; its attendance or application path has not been classified.
Public and private scores come from different models and are shown side by side, not blended into one ranking.
Greenwich School District
- Schools in district
- 15
- Rank in district
- #11 of 15
- District spending per student
- $31,488NCES F-33 · FY 2023 · This annual source is three years behind the current year.
- District child poverty rate
- 5.3%Census SAIPE · 2024
Cos Cob School is listed in Greenwich School District; a district label does not verify attendance for an address.
About Cos Cob School
Cos Cob School is a public elementary school in Cos Cob, CT, part of Greenwich School District, serving approximately 340 students in grades Kindergarten-5th with a 9.7:1 student-teacher ratio. It holds a MySchoolScout rating of 8.4 out of 10 and ranks #160 of 990 schools in CT. State assessment records show 73% math proficiency (multi-year average, 2009-2022) and 74% reading/ELA proficiency (multi-year average, 2009-2022).
Frequently asked questions
Common questions about Cos Cob School
What grades does Cos Cob School serve?
Cos Cob School serves students in grades Kindergarten through 5th.
How many students attend Cos Cob School?
Cos Cob School has an enrollment of approximately 340 students.
What is the student-teacher ratio at Cos Cob School?
The student-teacher ratio at Cos Cob School is 9.7:1. A lower ratio generally means more individual attention per student. The national average is approximately 16:1 for public schools.
How does Cos Cob School rank in CT?
Cos Cob School ranks #160 of 990 schools in CT.
What is Cos Cob School's MySchoolScout rating?
Cos Cob School has a current MySchoolScout rating of 8.4 out of 10. This score combines the level-appropriate components shown in the rating breakdown; equity data is shown separately for context.
What are the test scores at Cos Cob School?
Based on loaded state assessment records, Cos Cob School has 73% math proficiency (multi-year average, 2009-2022) and 74% reading/ELA proficiency (multi-year average, 2009-2022).
Is Cos Cob School a charter school?
No, Cos Cob School is not a charter school. It is a traditional public school operated by the local school district.
Is Cos Cob School a Title I school?
No, Cos Cob School is not currently a Title I school.
What does the Free & Reduced Lunch percentage mean for Cos Cob School?
14.1% of students at Cos Cob School qualify for free or reduced-price lunch. This is a commonly used indicator of economic need and provides important context when interpreting test scores.
School factsNCES Common Core of Data (CCD) (SY 2023–24)
- Grades
- Kindergarten – 5th
- Enrollment
- 340
- Student-Teacher Ratio
- 9.7:1
- Teachers (FTE)
- 35
- Type
- regular
- Setting
- Large Suburb
- County
- Connecticut Planning Region 9
- Chronic Absenteeism (SY 2022-23)
- 10.9%
- Phone
- (203) 869-4670
- Area population (ZIP 06807)
- 7,667
- Area average commute
- 28.9 min
- Area median age
- 39.3
Official sources & links
About this school's data
Every number on this page comes from a published source with a stated period. Where a source is partial, aging, or describes a surrounding area rather than the school, that limitation is named below.
- School directory (enrollment, grades, staff, contact)
- NCES Common Core of Data (CCD) · SY 2023–24 · Medium confidence
- Source period: SY 2023–24. A newer release may be available.
- MySchoolScout rating and rank
- MySchoolScout ranking model · Low confidence
- Vintage not available. Do not use this measure alone.
- Derived as a weighted blend of the component scores shown in Academics from state assessment, EdFacts growth, and NCES resource records.
- Math proficiency
- State department of education · 2022 EdFacts · Low confidence
- Older source: 2022 EdFacts. Use as historical context.
- Available for part of the eligible units; results may not represent the full area.
- Derived from source records rather than read directly from one field.
- Reading/ELA proficiency
- State department of education · 2022 EdFacts · Low confidence
- Older source: 2022 EdFacts. Use as historical context.
- Available for part of the eligible units; results may not represent the full area.
- Derived from source records rather than read directly from one field.
- Student progress (growth)
- NCES EdFacts · Mixed source periods · Low confidence
- Vintage not available. Do not use this measure alone.
- Available for part of the eligible units; results may not represent the full area.
- Derived as the fitted year-over-year slope of proficiency from multi-year assessment records.
- Neighborhood (income, housing, education)
- U.S. Census ACS 5-year estimates · ACS 2019–2023 5-year estimates · Low confidence
- Older source: ACS 2019–2023 5-year estimates. Use as historical context.
- Reported for the ZCTA for ZIP 06807; this does not measure the attendance area.
- Programs (AP/IB, athletics, gifted)
- CRDC via Urban Institute · SY 2021–22 · Medium confidence
- Available for part of the eligible units; results may not represent the full area.
- Source period: SY 2021–22. A newer release may be available.
Evidence periods: Rating mixed/unknown input periods; assessments multi-year average, 2009-2022; directory SY 2023–24
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