Wentzville Holt High School (Emil E. Holt Sr. High School, or simply Holt High School) is the oldest of the three high schools in the Wentzville R-IV School District and second oldest high school in St. Charles County, Missouri. With a 2014 enrollment of 1,728, Holt is the sixth largest high school in St. Charles County. Although officially known as Emil E. Holt Senior High School, it was known only as Wentzville High School until 2000, when "Holt" became a common addition to the name in preparation for the addition of a second high school in the district.