Thirty-two-year-old Derek Lofland of Greenwood was arrested by state police at his home Tuesday.
He is charged with three counts of fourth-degree rape, four counts of sexual solicitation of a child under 18 and 16 counts of unlawful sexual contact.
Lofland was being held at Sussex Correctional Institute on an $86,000 secured bond.
Investigators say Lofland and the girl developed a friendship in April that escalated into sexual contact while on school grounds, as well as at Lofland's home.
Lofland also allegedly texted the victim explicit sexual messages.