He is also accused of kissing the girl at a middle school basketball game.
The relationship was discovered when the student, who is now 18, asked her father if she could see Core socially.
Core is a substitute teacher and boys soccer and middle school basketball coach in the district, according to records.
The school has reported the allegations to the Champaign County Sheriff’s Office and the Ohio Department of Education and is not using Core as a substitute teacher. He is also banned from school property and activities, according to a letter dated March 5.
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