Cos Cob School
🇺🇸 Official data · 2025Cos Cob, Connecticut 06807 · Greenwich School District
#74 of 596 elementary schools in Connecticut
#908 of 50,301 nationally
About Cos Cob School
Cos Cob School is a public elementary located in Cos Cob, in the Greenwich School District school district of Connecticut, United States. It caters for Grades PK–5. In 2025 it enrolled 343 students. Traditional public schools run by a school district; free to attend.
Its Success Index (US) is 89.4 out of 100, placing it in the top 5% of elementary schools in United States and 74th of 596 ranked elementary schools in Connecticut. Its strongest component is students per teacher (93th percentile), and its weakest is reading proficiency (86th percentile).
Other published figures: enrollment 343.
Success Index (US) breakdown
Each component is a percentile against elementary schools across United States.
- Math proficiency (30%)74%
- Reading proficiency (30%)72%
- Community advantage (fewer free/reduced-price lunch) (25%)16%
- Students per teacher (15%)10.1
The Success Index (US) summarises published data about a school community. It is not a measure of teaching quality. Read the methodology.
Published measures
All figures published for Cos Cob School by the official sources.
- Enrollment
- 343
- Students enrolled in the latest NCES directory year.
- Free/reduced-price lunch
- 16%
- Share of students eligible for free or reduced-price lunch.
- Students per teacher
- 10.1
- Enrollment divided by FTE teachers; not class size.
- Reading proficiency
- 72%
- Share of tested students proficient or above (all students, all grades).
- Math proficiency
- 74%
- Share of tested students proficient or above (all students, all grades).
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Schools near Cos Cob School
Closest schools by straight-line distance, with their Success Index (US).
Central Middle School
Greenwich · Public middle · Grades 6–8
483 students · 1.1 km away
Greenwich High School
Greenwich · Public high · Grades 9–12
2,620 students · 1.2 km away
Eastern Middle School
Riverside · Public middle · Grades 6–8
797 students · 1.4 km away
Riverside School
Riverside · Public elementary · Grades K–5
440 students · 1.7 km away
Julian Curtiss School
Greenwich · Public elementary · Grades PK–5
236 students · 2.0 km away
International School At Dundee
Riverside · Public elementary · Grades K–5
342 students · 2.2 km away
North Mianus School
Riverside · Public elementary · Grades K–5
423 students · 2.5 km away
North Street School
Greenwich · Public elementary · Grades PK–5
411 students · 2.7 km away
Old Greenwich School
Old Greenwich · Public elementary · Grades PK–5
385 students · 2.8 km away
Westover School
Stamford · Public elementary · Grades K–6
624 students · 3.7 km away
Similar schools
Public elementary schools in Connecticut with a comparable Enrollment.
Barack H. Obama Magnet University School
New Haven · Public elementary · Grades PK–4
343 students
Bugbee School
West Hartford · Public elementary · Grades K–5
343 students
Royle Elementary School
Darien · Public elementary · Grades PK–5
342 students
Robert J. O'Brien School
East Hartford · Public elementary · Grades K–5
344 students
Noah Wallace School
Farmington · Public elementary · Grades K–4
342 students
International School At Dundee
Riverside · Public elementary · Grades K–5
342 students
Frequently asked questions
Is Cos Cob School a good school?
Cos Cob School has a Success Index (US) of 89.4 out of 100 (Top 5% of elementary schools in United States) and ranks #74 of 596 in Connecticut. The index summarises published data about the school community and, where available, attainment; it does not measure teaching quality, so visit the school and ask about support at your child's level.
Where does Cos Cob School rank in Connecticut?
Cos Cob School ranks #74 of 596 elementary schools in Connecticut and #908 of 50,301 nationally on the Success Index (US) (2025 data).
How many students attend Cos Cob School?
Cos Cob School had 343 students in 2025.
Is Cos Cob School a elementary school or a high school?
Cos Cob School is classified as a elementary covering Grades PK–5. It is a public school.
What other schools are near Cos Cob School?
There are 10 schools within 15 km of Cos Cob School; they are listed on this page with their Success Index (US) and distance, and can be compared side by side.