The Governor’s Academy (Massachusetts) : The oldest continuously operating independent boarding school in the United States

The school was founded two years after the death of William Dummer, who funded it in his will. Dummer had been lieutenant governor and acting governor of Massachusetts for many years, and led the colony through a difficult period in the earlier 18th century: fighting off forays by French and Indians during what became known as Dummer's War in the 1720s.

He also served as an early overseer of Harvard College. He was from a prominent colonial family with his brother Jeremiah Dummer having been a principal founding benefactor of the College of New Haven which later became Yale University. As the Boston Latin School only accepted students from the city of Boston, the need arose for schools in more outlying areas to prepare students for college—the only ones existing at that time in New England being Harvard and Yale; Brown and Dartmouth were founded a few years afterward.

In that context, the Dummer Charity School or Dummer Grammar School commenced operation in 1763 pursuant to the will of Governor Dummer with Samuel Moody as its first headmaster. In 1782, the Dummer school was officially incorporated as the Dummer Academy, whose graduates in this era comprised approximately 25% of the undergraduate student body at Harvard. Most children in this era were home-schooled with pre-college education ending around the age of 14, with youths thereafter going on to college or entering the workforce. Thus most college freshmen tended to be the age of high school freshmen today.

Students study in small classes, with a student-to-teacher ratio of 5-1. Advanced Placement courses are offered in nearly 22 subjects, from mathematics and science to art, foreign languages, English and history. Foreign language classes are offered in Chinese, French, Spanish, German and Latin. Eighty-five percent of faculty live on campus and serve as dorm parents and coaches as well as classroom teachers. More than 70% have advanced degrees, with several having earned terminal degrees in science, law, education and medicine.

According to wikipedia