Cos Cob School
Score 66.4/100: better than 66% of Connecticut elementary schools on 2024-25 state tests. Schools are only compared with others of the same type in the same state. How we score schools
Performance (state tests, 2024-25)
Performance Index (0-100) on state tests in Connecticut, all students. Colored bars are green when the school is at or above the average for similar Connecticut schools.
Results over time
How this school's published results have moved year by year.
All 3 published results by grade and test
As published by Connecticut State Department of Education. "Hidden" means the state didn't publish the result to protect student privacy.
| Subject | Grade | Test | Result | Students tested |
|---|---|---|---|---|
| English language arts | All grades | CT NGA Indicator 1 Performance Index (SBAC ELA/Math, NGSS Science) | 75.5 | — |
| Math | All grades | CT NGA Indicator 1 Performance Index (SBAC ELA/Math, NGSS Science) | 75.2 | — |
| Science | All grades | CT NGA Indicator 1 Performance Index (SBAC ELA/Math, NGSS Science) | 72.5 | — |
School profile
- Grades
- PK-5
- Students
- 340
- Type
- Elementary school
- Charter school
- No
- Program
- Regular
Students
District and location
Contact
Cos Cob, CT 06807
"Typical" is the middle (median) elementary school in Connecticut. Higher or lower is not in itself better or worse. Address, phone and website are as the state reported them to the U.S. Department of Education for 2024-25, so check with the school before visiting. School details: U.S. Department of Education, Common Core of Data (enrollment 2023-24, lunch eligibility 2024-25).
Nearby elementary schools
Straight-line distance. Check the district's attendance zones: living close to a school doesn't guarantee a place.
Explore schools around Cos Cob
Location
Official sources
Every figure on this page comes from published government data. Check the originals here; we refresh when states release new results.
U.S. Department of Education, National Center for Education Statistics, Common Core of Data (CCD): school directory, grades served, enrollment and free/reduced-price lunch, 2023-24 and 2024-25. Spotted a mistake? Tell us.
Cos Cob School at a glance
Cos Cob School is a public elementary school in Cos Cob, Connecticut, serving grades PK-5. It is part of Greenwich School District. It has about 340 students (a typical Connecticut elementary school has 356). About 16% of students are eligible for free or reduced-price lunch, compared with 37% at a typical Connecticut elementary school, which is useful context when reading test results.
In 2024-25 state tests, 75.5 in English language arts (similar schools: 69.7) and 75.2 in math (similar schools: 67.6) reached the performance index shown (Performance Index (0-100)). On our score, which compares it only with other Connecticut elementary schools, it scores 66.4 out of 100: better than 66% of them, ranking #157 of 466. Its English language arts result was broadly unchanged from the year before. This overview is generated automatically from published state and federal data; figures are rounded, and you can check the originals via the official sources above.
Page updated 2026-10-12.