According to police, Callie Miller, 25, turned herself in on Monday. She was booked into the Oklahoma County Jail, and has since bonded out on a $75,000 bond.
Miller has been charged with two counts of second-degree rape and one count of soliciting sexual contact with a minor.
A search warrant filed by Oklahoma City police said Miller taught both students last year at Capitol Hill High School, and she started contacting them both in August 2013.
OKCPS officials released a statement on August 1, 2014 and said that during the investigation, Miller was placed on paid administrative leave from December 2013 to May 2014. Officials said Miller separated from the district in May 2014 and is no longer an OKCPS employee.