Cos Cob School

Cos Cob School is a medium-sized elementary school in Connecticut, located in Cos Cob. Classes run from pre-K through 5, and the school has 343 students.

Cos Cob School is one school in Greenwich School District, a system of 15 schools with 8,377 students.

A majority of students at Cos Cob School, 67%, are White. Next come 20% Hispanic, 5% Asian, and 5% multiracial. The chance that two students picked at random at Cos Cob School belong to different racial or ethnic groups, known as the diversity index, is 50%.

Cos Cob School's 34.3 full-time-equivalent teachers put its ratio at 10.0:1. That ratio is under the 12.6:1 average for elementary schools in Connecticut. The school's rate of free or reduced-price lunch eligibility is 16%. Compared with the 33% average for public schools in Western Connecticut Planning Region, the school's rate is lower.

Cos Cob School is graded B+ by allk12, scoring above 67% of Connecticut public elementary schools once test results, poverty-adjusted performance, and the recent trend are combined.

According to the American Community Survey, in Western Connecticut Planning Region, median household income is about $128,188, the share of adults with a bachelor's degree or higher is 56%, and about 5% of people live in poverty. A total of 149 public schools operate in Western Connecticut Planning Region, serving about 90,520 students.

Central Middle School is located about 0.7 miles from Cos Cob School. Within five miles are at least 8 other public schools.

NCES assigns Cos Cob School the locale Suburb: Large, meaning in a suburban area outside a principal city, within an urbanized area with a population of 250,000 or more.

Federal counts put enrollment at 362 in 2020-21 and 343 in 2024-25, a 5% decrease. Staffing shifted too: the ratio moved from 11.7:1 to 10.0:1.

Parents and students can post about enrollment questions, class placement, and PTA news at Cos Cob School. Questions from prospective families are welcome too.