Cos Cob School

As a mid-tier primary school in Cos Cob, Connecticut, Cos Cob School hosts 343 students from grades pre-K through 5, operated by Greenwich School District.

Greenwich School District comprises 15 schools with combined enrollment of 8,377 students; Cos Cob School is among them.

Looking at the student body, Cos Cob School reports that White students make up the majority at 67%. Other groups include 20% Hispanic, 5% Asian, 5% multiracial.

On the resource side, The school employs 34 full-time-equivalent teachers, for a student-teacher ratio near 10.0:1. Statewide, the average ratio sits near 12.6:1, putting Cos Cob School tighter than the state norm the norm. Around 16% of the student body qualifies for free or reduced-price meals, a number frequently used as a low-income enrollment indicator. By comparison, Western Connecticut Planning Region runs at roughly 33%, so the school's eligibility rate is meaningfully below the surrounding baseline.

In the area at large, census data for Western Connecticut Planning Region shows median household income runs about $128,188, about 56% of the adult population holds a bachelor's degree or above, and census figures put the poverty rate at about 5%. Across Western Connecticut Planning Region's 149 public schools (combined enrollment of about 90,520 students), Cos Cob School is one campus in the mix.

Nearest neighbor: Central Middle School, around 0.7 miles off. Within five miles, there are 8 other public schools.

Cos Cob School operates from a commuter-belt location.

Trend over the last 7 years. Cos Cob School's enrollment has fell 21% since 2018, when it stood at 434 (now 343). Class-load math has pulled in: from 11.5:1 in 2018 to 10.0:1 in 2025.

On this page, members of the Cos Cob School community share and discuss school events, parent volunteer needs, and clubs. The community welcomes input from current and former families.