Northfield Mount Hermon School, often called NMH, is a co-educational preparatory school in Gill, Massachusetts in the United States. It is a member of the Eight Schools Association.

Commonwealth School is a private high school of about 140 students and 35 faculty members located in the Back Bay neighborhood of Boston, Massachusetts, United States. It is accredited by the New England Association of Schools and Colleges

Milton Academy is a coeducational, independent preparatory, boarding and day school in Milton, Massachusetts consisting of a grade 9–12 Upper School and a grade K–8 Lower School. Boarding is offered starting in 9th grade. It is a highly selective school, accepting only 14% of applicants in the 2020–21 school year.

The Emma Willard School, originally called Troy Female Seminary and often referred to simply as Emma, is an independent university-preparatory day and boarding school for young women, located in Troy, New York, on Mount Ida, offering grades 9–12 and postgraduate coursework.

The College Preparatory School is a four-year private high school in Oakland, California. The school's motto is Mens Conscia Recti, a Latin phrase adapted from Virgil's Aeneid that means "a mind aware of what is right".

The Loomis Chaffee School is a selective independent, coeducational, college preparatory school for boarding and day students in grades 9–12, including postgraduate students, located in Windsor, Connecticut, seven miles north of Hartford.

Deerfield Academy is an elite coeducational preparatory school in Deerfield, Massachusetts. Founded in 1797, it is one of the oldest secondary schools in the United States. It is a member of the Eight Schools Association, the Ten Schools Admissions Organization, and the Six Schools League.

Primoris Academy is an independent private school located in Westwood, NJ, serving the passionately curious. Primoris Academy students are encouraged to explore interests with the mentorship of supportive faculty, discover complex solutions through critical thinking, and collaborate with peers that share the same desire to learn.

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Lake Forest Academy is a co-educational college preparatory school for boarding and day students in grades 9 through 12. The school is located on the North Shore in Lake Forest, Illinois, United States, about 30 miles north of Chicago.