[citation needed] The original high school building now houses the Green Lantern Senior Center in Wentzville.

Herbert "Soby" Sobolewski suffered a heart attack during the previous year while directing traffic near a tractor-trailer crash on U.S. Highway 40 (now Interstate 64) near Wentzville.

[5][6][7] In 1969, the high school was officially named after Emil E. Holt, a community leader and president of the Wentzville State Bank.

Despite the formal designation, Holt's name was rarely used in reference to the high school over the next 30 years.

[8][9] In 2007, a two-story addition was completed on the north side of the building, adding 26,426 square feet of new space including six new classrooms and two science laboratories.

The movement resulted in swift backlash from most students and the Wentzville community, and was met with a counter petition from a recent Holt alumna with nearly five times more supporters to keep the Indian mascot.

The planning team behind the move toward block scheduling consisted of teachers, students, parents, and administrators, and it began meeting in 1993.

Some board members cited flat standardized test scores over the past few years as another reason for the change.

Adams also referenced studies that indicate block scheduling results in higher grades but lower achievement.

A couple of years after the "Holt" name was re-emphasized for the school, new athletic coaches and staff began re-branding the teams with new logos and a change in colors to the current Navy and Vegas Gold.

Holt's MSHSAA sanctioned sports compete in the South Division of the Gateway Athletic Conference.

In 2011, the Holt hockey team defeated Rockwood Summit High School 3–2 in overtime in the championship game at Scottrade Center to become the first high school hockey team from St. Charles County to win the Wickenheiser Cup championship.

In March 2013, the Holt Indians captured their second state championship in three years, when they defeated the Duchesne Pioneers in the Wickenheiser Cup title game at Scottrade Center.