[3] The Longmont High School football team won the national championship in 1908.

The school is perhaps best known, however, for its record streak, starting in 1988 and ending in 1992, in which the Trojans went 45–0, winning three consecutive championship crowns.

This remains the longest winning streak in large-school Colorado football history.

The Longmont High School Band commissioned "Joy Revisited" by Frank Ticheli in 2005.

The Longmont High School Band commissioned "Ostinato" by Richard Saucedo in 2010[5] The Longmont High School Drumline has competed in Percussion Scholastic World (PSW) in 2001; Percussion Scholastic Open (PSO), winning two state championships from 2002 to 2006; Percussion Scholastic National A PSNA (in RMPA competition 2009), from 2007 to 2009, winning state in 2009; and in Percussion Scholastic A (PSA) from 2010 to present.