Culpepper was born to a single mother, Barbara Henderson, who is the sister of former NFL linebacker Thomas "Hollywood" Henderson. While his mother was pregnant with him, she was serving time for armed robbery. Culpepper was adopted when he was a day old and raised as one of more than 15 children of the late Emma Lewis Culpepper, who worked in the correctional facility where his mother was held. They lived in Ocala, Florida, where Culpepper attended Vanguard High School. He played football, coached by Alex Castaneda, one of five finalists for the 2000 NFL High School Football Coach of the Year Award, as well as basketball and baseball. After his senior season in 1994, he was named Mr. Football in the state of Florida. In 2007, Culpepper was named to the FHSAA's All-Century Team that listed the top 33 football players in the state of Florida's 100-year history of high school football.