[6] GBN serves most of Northbrook, some unincorporated portions of Cook County, and a small section of Glenview.

But as Northbrook grew due to American suburbanization, more space to accommodate students was needed, warranting its closure and the construction of a new high school.

In the spring of 1996, a three-year renovation and construction project involving the science facilities and the "A" wing was built.

A successful referendum in 2006 enabled renovation and addition to a second floor of the schools "F" wing, state of the art Fitness Center, complete renovation and additions to the Music Area, and a sun-filled main entrance, which were completed in 2009.

[11] Throughout the years, Glenbrook North High School has received state and national recognition for its academic excellence.

In the late 1950s, when Glenbrook was less than 10 years old, it was named one of the top 44 high schools in the country by a survey in a national magazine.

[13] On January 22, 1997, President Bill Clinton visited the school to deliver a speech about education initiatives.

[15]Less than a month later, Bill Clinton referenced his visit to the school and these achievements in his 1997 State of the Union on February 4, 1997.

The event was a "Powder Puff" girls' football game between members of the junior and senior classes.

The "game" took place on May 4, 2003, in Chipilly Woods, part of the Cook County Forest Preserve District.

During the event, about 20 junior class participants were covered in paint, urine, feces, and animal guts.

[19] The plaintiffs and the school district reached an agreement where the expelled students would have their diplomas mailed to them but would not be able to participate in graduation ceremonies.

[20] Local law enforcement authorities investigated the hazing incident and filed charges against 15 students for assault and battery.

[23] A community-wide task force was established by the Northbrook Police Department Community Services Division after the hazing incident.

[28] For the 2021 school year, 71.4% of students were White, 0.5% were Black, 5.4% were Hispanic, 17.9% were Asian, 0% were Native American, 0.1% were Pacific Islander, and 4.8% were of two or more races.

[42] Glenbrook North offers many sports including, but not limited to baseball, basketball, bowling, cheerleading, cross-country, football, golf, ice hockey, lacrosse, soccer, softball, swimming, tennis, track, and volleyball.

[44] The following GBN teams have won IHSA sponsored state championship tournaments in the listed years:[45]

On December 28, 2005, the school's basketball program gained national media attention[46] when Jon Scheyer scored 21 points in the final 75 seconds of a comeback attempt against Proviso West.

An accurate, up-to-date list is difficult to keep, as clubs are added and dropped as students graduate or lose interest.