The Bay State Conference was established in 1958 and included ten charter member schools. In the fall of 1990, the conference expanded to 12 schools with the additions of Brookline and Newton North, and split into two divisions. The divisions were originally based on enrollment and named after Mr. Fran Carey and Mr. Fred Herget; they are known as the Carey Division and the Herget Division of the Bay State Conference (BSC). In 1991, Framingham North and Framingham South merged into one school, creating an opening in the BSC, filled when Weymouth was admitted to the BSC in 1997. Beginning in the Fall of 2018, divisional placement was altered on the basis of geography. Divisional alignments are reviewed in October of odd years.1

Conference as of 2026 — 10 schools

Carey Division Herget Division
Brookline Braintree
Framingham Milton
Natick Needham
Newton North Walpole
Wellesley Weymouth

Conference as of 2018 — 10 schools

Norwood left for the Tri-Valley League. The schools were realigned by geography.

Carey Division Herget Division
Brookline Braintree
Framingham Milton
Natick Needham
Newton North Walpole
Wellesley Weymouth

Conference as of 2017 — 11 schools

Dedham left for the Tri-Valley League.

Carey Division Herget Division
Braintree Milton
Brookline Norwood
Framingham Walpole
Natick Wellesley
Needham Weymouth
Newton North  

Conference as of 1997 — 12 schools

Weymouth joined.

Carey Division Herget Division
Braintree Dedham
Brookline Milton
Framingham Norwood
Natick Walpole
Needham Wellesley
Newton North Weymouth

Conference as of 1991 — 11 schools

Framingham North and South merged.

Carey Division Herget Division
Braintree Dedham
Brookline Milton
Framingham Norwood
Natick Walpole
Needham Wellesley
Newton North  

Conference as of 1990 — 12 schools

Brookline and Newton North joined. The Bay State Conference formed two divisions.

Carey Division Herget Division
Braintree Dedham
Brookline Framingham South
Framingham North Milton
Natick Norwood
Needham Walpole
Newton North Wellesley

Conference as of 1958 — 10 schools

A single undivided conference.

Braintree
Dedham
Framingham North
Framingham South
Milton
Natick
Needham
Norwood
Walpole
Wellesley