Herbert Hazelman is best known for his 40-year tenure (1936-1942, and 1944-1978) as the director of the Greensboro Senior High School and Grimsley High School bands. In 1936, when Mr. Hazelman was appointed as the sole instrumental teacher for the city schools (reviving the program following the Depression), he became responsible not only for the band and orchestra programs at GHS, but also for the junior high and elementary instrumental programs in Greensboro as well. Additionally, after expressing concern for band programs at the black schools, Mr. Hazelman found qualified music teachers to be placed at the appropriate schools.

At the height of Mr. Hazelman's program, seven band teachers were working with the program at Grimsley, in addition to their other school assignments. The program at GHS grew so large that by the 1960's the school had two full concert bands, along with swing (later jazz) and marching bands. In 1954, the marching band was invited to perform during a nationally televised halftime show of a Washington Redskins NFL football game at Griffith Stadium in D.C.

Under Herbert Hazelman, the GHS band achieved a number of "firsts." Besides the "twin band," the band was the first from North Carolina to appear at the Mid-West Band Clinic in Chicago (1954), the first high school band to have a balanced clarinet choir, the first to have a regularly scheduled television broadcast series, the first to perform for the Canadian Bandmasters Association, and the only high school band ever to have hosted the national meeting of the American Bandmasters Association (1963). GHS was awarded the honor of having a composer-in-residence on staff for two years (1960-1962), sponsored by the Ford Foundation as part of its "Young Composers Program." The program leaders informed Mr. Hazelman that GHS, based on the superior quality of its music groups, would receive the finest composer they had, John Barnes Chance.

Mr. Hazelman was highly respected by educators, composers, and conductors throughout the United States. He was a member of The American Bandmasters Association, and also was a charter member of the North Carolina Symphony (as an oboe player), the North Carolina Bandmasters Association, and the North Carolina Association of Educators. Mr. Hazelman composed music for orchestra and chorus, including Moronic Dance which he composed at age 17 and which was included in the very first concert of the North Carolina Symphony in 1932. During this same period, the National Symphony Orchestra in Washington, D.C. played one of Mr. Hazelman's pieces, where he was honored by being seated beside the then First Lady, Mrs. Herbert Hoover.

Mr. Hazelman was instrumental in the design and building of the music building at GHS which was constructed in 1956, and which was named in his honor as "The Herbert R. Hazelman Music Building" in 2004.

His awards and recognition include: upon retirement in 1978, Mr. Hazelman received letters of recognition from The Governor of North Carolina, The Mayor of Greensboro, The Mayor of Asheville (where he grew up), The Chairman of the Education Department at UNC-Chapel Hill (from which he received a BA degree in 1935); The 1978 Whirligig (GHS yearbook) was dedicated to Mr. Hazelman; North Carolina Music Educators Association Honorary Life Membership; Greensboro Chamber of Commerce O'Henry Award; Greensboro Music Academy's first recipient of its Community Citizen Award; Greensboro Symphony Orchestra / City of Greensboro Award for "outstanding contributions to music and in appreciation of his commitment to the musical growth of the citizens of Greensboro"; and the North Carolina Bandmasters Hall of Fame.

Upon retirement, Mr. Hazelman continued his role in music education as a volunteer with the Shepherd's Center, teaching music appreciation classes.

Several scholarships are named in his honor including the Greensboro Music Academy's Herbert Hazelman Scholarship, and the Grimsley High School Band Boosters' Herbert Hazelman Scholarship.