Founded in 1901, the school serves the Chicago suburbs of Wilmette, Kenilworth, Winnetka, Glencoe, and Northfield, as well as parts of Northbrook, Glenview, and unincorporated Cook County.

In 1965, the New Trier West Campus (which, as of 2023, serves the school's first-year students) opened in the village of Northfield.

By 1970, New Trier was home to the nation's first public high school-based CCTV instructional station, ITV, which broadcast educational programming to township elementary schools via microwave signals.

To accommodate the growing baby boomer student body, voters approved a referendum for New Trier to purchase 46 acres of land in Northfield.

The resulting modernist design was widely noted in secondary education architecture literature and practice and emulated by Winnetka's Carleton Washburne junior high school several years later.

By then, enrollment had declined enough for the board to bring all students under one roof, close the former New Trier West, and convert the Northfield campus into a community recreation space.

The demographer, however, expressed caution about relying on predictions that exceeded ten years, stating in part that ".

.after 10 years, greater risk emerges of unanticipated events invalidating even the most scientifically-based projection methods."

The Campus was retained and subsequently rented to various entities until it was again needed as additional space for a growing NT student population.

The Coalition has never been acknowledged publicly for its significant role as a catalyst in retaining the 42.5-acre New Trier West Campus.

Among other claims, the article stated that "New Trier kids who smoke pot" were "by all accounts more than three-fifths of the student body," compared with national averages at the time closer to 33%.

However, on the school's WNTH radio program, the writer acknowledged that the "three-fifths" claim had been inadvertently rewritten during the editing process in such a way that seemed to imply that more than 60% of New Trier students may be regular users of marijuana, whereas that figure should have been clearly labeled as the portion of students who had ever used marijuana, including many who had used it only once or twice [18] In 2017, the school neared completion of a $104.9 million renovation and addition project at its East Campus, which replaced three aging buildings on the west side of the campus with the addition of a new student cafeteria, a new library, more than two dozen classrooms for core English, math, social studies, language and business program classes, new art labs, applied arts classroom spaces in the basement for STEM (science, technology, engineering, and math) programming, space for the school's radio and broadcasting programming, two green roofs, and two new theaters.

[22] As of 2017[update], the New Trier Township High School Board of Education's members are mostly from Glencoe and Wilmette.

[24] As of September 1, 2017, the current superintendent of New Trier Township High School District 203 is Dr. Paul Sally.

[28] Since the late 1990s, the Board of Education has been examining how to encourage students to pursue a strong academic career without focusing too much on their class rank.

[citation needed] The school was identified as "quite possibly the best public school in America" by Town & Country, in a six-page article on New Trier that cited the "rich" and "demanding" curriculum, extensive arts and activities, strong participation in athletics, and faculty of the caliber typically found teaching at good colleges.

[citation needed] According to an article by the University of Michigan Department of Psychology, "New Trier students outperform their Illinois classmates on every conceivable measure.

The student-run Soundtraks Club produces all 24 concerts a year, webcast live on the internet at ntjazz.com,[33] on local cable television, and in stereo on WNTH radio.

[35] In April 2006, the school's Concert Choir and Symphony Orchestra performed in New York City at Carnegie Hall.

In the summer of 2000, the school's Jazz Ensemble, Chamber Orchestra, and Bluegrass Band enjoyed a successful two-week concert tour of China.

[36] Although some date back to the founding of the school, and have strong traditions (like Tri-Ship, the all-boys service club), others are much newer and consist of only a few members.

The Trevian mascot was chosen to recognize that immigrants from Trier, Germany, largely settled the Grosse Pointe area of Wilmette.

[citation needed] New Trier's biggest conference rival is Evanston Township High School.

New Trier's biggest non-conference rival is Loyola Academy, which is located in Wilmette, just down the road from the Northfield campus.

[55][56] Having won state 16 times, New Trier has consistently demonstrated excellence, qualifying for the national tournament every year since 2002.

[54] Beyond these team achievements, New Trier students frequently earn individual accolades, having collectively won nearly 100 national medals since 2002.

The NTSC has consistently placed in the top 5 of all teams in the state of Illinois,[61] and has been recognized by USA Swimming as a Silver Medal Club for the past four years.

New Trier's Lagniappe-Potpourri is an annual student-written, student-choreographed, student-composed, student-directed, student-managed, student-built, and student-performed variety show.

[69] Each of the four official class governments (Sophomore and Junior Steering Committees and the Freshman and Senior Senates) makes significant annual donations to various philanthropic causes throughout the community, state, country, and world.

[73] Scenes from Uncle Buck and Home Alone were shot at the high school's west campus in Northfield.