The school's colors are navy blue and white, and its teams are known as the "Whirlies" (originally the "Purple Whirlwind") depicted with a tornado-like symbol.

By 1910, this building was outgrown, so for one year (1910–1911) GHS was moved next door to the Lindsay Street Grammar School.

In the fall of 1929, GHS moved to its current Westover Terrace location, when it became Greensboro Senior High School.

In 1934, as part of the New Deal's Civil Works Administration (CWA), two large murals were painted in the GHS auditorium by Raleigh artist James A. McLean: "Energy" and "Education".

Because of increasing difficulty in finding matching shades of purple for athletic and band uniforms, the colors were changed—by vote of the student body in March 1951—to navy blue and white.

Local papers, in an attempt to have variety when referring to GHS's teams (and to save space in headlines) came up with the name "Whirlies" in 1941.

On August 20, 2008, then Presidential candidate, and soon to be 44th President of the United States, Barack Obama played basketball with former SportsCenter anchor Stuart Scott in the Sawyer Gym.

In 2013, Grimsley had the graduation of a fifth-generation GHS student, which became statewide news because of its rarity for a public school.

In 1995, the International Baccalaureate (IB) program was instituted at Grimsley, after two years of preparation by the school under Principal Tom Penland.

Grimsley was only the fourth high school in North Carolina, and the first outside Charlotte, to offer the IB program.

Connected to the Sawyer Gym is the John Gordon Dewey '71 Memorial Swimming Pool, which opened in 1976 but became defunct in December 2011 after a large storm uprooted part of the roof.

Across Campus Drive are the other athletic facilities, the Robert B. Jamieson Football Stadium (1949, named in 1975), which included a track (1958–2012) and the Sigmund Selig Pearl Memorial Field House (1950), and beyond the football stadium, the Willie Young/Lewis McCall Memorial Baseball Field (1953, named in 1974 and 2007), and the Cross Country trail (1962).

It has been said that the use of hard clay in the set up of walkways in 2002-03 created the infamous "Lake Grimsley" in the front lawn.

Lake Grimsley (as students call it) is a large area of standing water that forms when it rains heavily or for a long period of time.

Grimsley is a 4-A school with a strong athletic program, including sports teams in football, basketball, baseball, tennis, swimming & diving, golf, wrestling, cross country, track & field (both winter and spring), soccer, softball, volleyball, field hockey, and lacrosse.

Grimsley has won the NCHSAA 4-A Wachovia Cup (for the most outstanding 4-A athletic program in North Carolina) five times: 1985, 1986, 1987, 1988, and 1990.

The GHS cross country trail (1962) is in the woods behind Kiser Middle School and the football stadium and baseball field.

This rivalry is celebrated every year with a spirit week before the football game, which usually attracts crowds of close to 10,000, the capacity of Jamieson Stadium.