Northfield Mount Hermon School, commonly referred to as NMH, is a co-educational college-preparatory school for both boarding and day students in grades 9–12 and postgraduates. NMH is a selective school with an acceptance rate of 32%. The school is located on the banks of the Connecticut River, with the majority of the campus being located within the towns of Bernardston, Northfield, (West Northfield), and Gill, Massachusetts.

Originally two neighboring schools, (the Northfield School for Girls founded in 1879, and the Mount Hermon School for Boys founded in 1881) NMH merged into a single institution in 1971 and consolidated on one campus in 2005.

NMH is a member of the Eight Schools Association, a group of elite high schools established in 1973 and comprising Phillips Academy (known as Andover), Phillips Exeter Academy (known as Exeter), Choate Rosemary Hall (known as Choate), Deerfield Academy, Hotchkiss School, Lawrenceville School, and St. Paul's School.^[1]

NMH offers more than 200 courses, including AP and honors classes in every discipline. Every semester, students take three major courses, each 80 minutes long, as opposed to five 50-minute classes which are more typical of high schools. This "College-Model Academic Program" allows students to spend more time with their teachers and immerse themselves more deeply in academic subjects. NMH employs 91 full-time teaching faculty members, 60 percent of whom have advanced degrees. The average class size at NMH is 11 students; the student-to-teacher ratio is 6 to 1.

Students are required to participate in cocurricular activities every semester; these include athletic teams, performing-arts ensembles, volunteer work on and off-campus, and activities such as working for one of the school's four student publications. Students may join an extensive array of extracurricular clubs, organizations, and affinity groups.

Students involved in visual and performing arts courses, as well as NMH's performing ensembles, are supported by the Rhodes Arts Center. (See more under "Arts Programs")

With more than 60 athletic teams in 20 interscholastic sports, NMH offers one of the broadest athletic programs among secondary schools in the U.S. and currently holds the national prep championship title in boys' basketball and New England championship titles in girls' crew, wrestling, and numerous individual swimming and track and field events. NMH offers an extensive outdoor education program in addition to its competitive teams.

Each student is required to hold a job on campus, working four to five hours a week for a total of 120 hours each school year. This contribution to the operation of the school stems from the school's founder, Dwight Lyman Moody, and his desire for students to understand the value of manual labor.

The school was founded by Protestant evangelist Dwight Lyman Moody as the Northfield Seminary for Young Ladies in 1879 (later called the Northfield School for Girls) and the Mount Hermon School for Boys in 1881. Moody built the girls' school in Northfield, Massachusetts, the town of his birth, and the boys' school a few miles away in the town of Gill. Moody's goal was to provide the best possible education for young people without privilege, and he enrolled students whose parents were slaves as well as Native Americans and people from other countries, which was unprecedented among elite private schools at that time. Moody sent out students who founded schools and churches of their own. For example, a protégé of Moody founded Moores Corner Church in Leverett, MA. Moody viewed Christian religious education as an essential objective of his schools. Under subsequent administrations, the schools grew more theologically liberal and ultimately became non-denominational. Today, NMH offers diverse ways to pursue religious studies and personal spirituality.

By 1913, the schools were operated under the single moniker "The Northfield Schools," but remained separate institutions until 1972, when the two schools merged to become Northfield Mount Hermon, continuing to operate with two coeducational campuses. In 2005, the school consolidated its students and classes onto the Mount Hermon campus. This decision by the board of trustees stemmed from a belief that students would receive the best possible education in a smaller, more close-knit community, and from a desire to focus the school's resources on educational programs and maintain one campus instead of two. Before consolidation, the school enrolled approximately 1,100 students per year; the student body has now settled at 650, making the admission process even more selective.

In June 2016, The Trust for Public Land and the Massachusetts Department of Conservation and Recreation ensured the complete and permanent protection of 1,300 acres of forest land which was previously the Northfield campus and owned by the Northfield Mount Hermon School for over a century. Although now a permanent part of the Northfield State Forest, it had been the largest parcel of unprotected land in the Commonwealth of Massachusetts. The property includes woodlands, trails and a reservoir which will be managed by the DCR to ensure public access for recreation as well as serve as important habitat for wildlife.^[2]

NMH's current head (interim) is Charles A. Tierney III. Brian H. Hargrove will become NMH's 12th head of school, effective July 1, 2019.

All students are required to participate in some form of physical education every term, which is not limited to interscholastic sports. The school fields over 60 teams (including junior varsity teams) in 20 different sports. The football team was abolished after the 2013 season, but otherwise most other major sports are offered, and several programs (e.g., boys' basketball, girls' swimming and both boys' and girls' cross-country) are regional and/or national powerhouses.

Mount Hermon claims to invented the sport of Ultimate Frisbee in 1968.^[3]

The 65,000-square-foot (6,000 m2) Gold LEED certified Rhodes Arts Center (at right) is the home of all of the arts programs at NMH. It houses two concert performance spaces, a black-box theater, two dance studios, an art gallery, classrooms, art studios, practice rooms, and faculty offices. Additionally, the RAC is home to the Class of 1958 Carillon, which was originally installed in Sage Chapel in 1924. The funds to make the move possible were spearheaded by the combined Mount Hermon and Northfield classes of '58. It can be played via an electronic keyboard situated in the bottom of the bell-tower. Memorial Chapel houses the school's own tracker action organ. Andover Organ Company Opus 67, completed in December 1970 and donated by Kenneth H. Rockey is a 2-manual 27-stop, 37-rank tracker organ with a pedal compass of 30, and a manual compass of 56.^[4]

Performing groups include:

NMH also produces an annual arts and literary magazine, Mandala, as well as two student-run newspapers, The Bridge and The Hermonite.

Many of the activities that NMH students are involved in are considered classes or part of the work program; others are organized outside the curriculum. NMH's Student Activities office provides support, services, and resources for student organizations, including places to meet, materials, and funding.^[5]