The centrally-located, nearly two-acre lot on which the building sits originally housed the homestead of politician George B. Upham.

The original school building contained four classrooms, a basement for heating and facilities, and a function hall on the top floor.

He also donated life-size portraits of George Washington and Daniel Webster, which still hang on the walls of the auditorium, and a Chickering concert grand piano.

The front of the building was expanded, adding a laboratory, classroom, a manual training room in the basement, and a headmaster's office.

Enrollment was at 434 in 1929, and a third subsequent expansion added an annex of fifteen classrooms, a gymnasium, and a remodel of the auditorium and older portions of the building.

[4] Its most recent renovation, completed in 2014, cost more than $12.6 million and restored original hardwood floors and other architectural elements, brought the facilities up to code, and addressed many long-standing structural issues.

The front of the building is the original structure, built in 1868, which consists of three floors of classrooms (including lab facilities for science classes) and administrative offices.

Stevens also offers courses in conjunction with the local Sugar River Regional Technical Center, and specific courses that offer credit within the Community College System of New Hampshire Stevens High School's colors are red and black, and its mascot is the cardinal.

[13] Its varsity sports include baseball, football, softball, basketball (boys and girls), golf, spirit team, cross country, skiing, swimming, field hockey, soccer (boys and girls), tennis, track & field, and bowling (co-ed).

[12] The school's extracurricular activities include Amnesty International, Interact, Color Guard, Jazz Band, Stevenaires, St. Paul's Summer Program, Key Club, Literary Club, Fall Production, Comedic Acting, Senior Play, Honors Theater, Musical Theater, National Honor Society, Environmental Club, Envirothon Team, Newspaper (Journalism), Student Council, Peer Outreach, Project Challenge, Boy's State, Girl's State, Granite State Challenge, and Quiz Bowl.