Boston English was created at the urging of the Massachusetts Charitable Mechanics Association and was modeled after the Royal High School in Edinburgh, Scotland.

Boston English ended its policy of single sex education and admitted girls to become coeducational in 1972, 151 years after its founding.

Its first site was on Derne Street at the rear of the Massachusetts State House and is marked by a metal historical commemorative plaque.

English High was created originally to educate working-class schoolboys in preparation for business, mechanics, and engineering trades as opposed to "Latin-grammar" schools like Boston Latin that prepared schoolboys for the college, ministry and scholarly pursuits, and private academies that were open only to affluent residents.

Its original curriculum consisted of such courses as English, surveying, navigation, geography, logic, and civics as well as a strong emphasis on mathematics.

English High School has an English-Language Learners program, which was run for many years by Francisco Ruiz.

Originating at the high school level, the program now serves grades 4–12 (roughly, ages 10–18).

Selected cadets also attend a summer leadership camp at Fort Devens, MA[clarification needed] in place of school for one week in June where they do activities such as obstacle courses, aquatics, rifle marksmanship, and rappelling off of 30 and 60-foot towers.