Authorities say Rachel Wrobel, a former teacher at Liberal High School, has been formally charged with one count of unlawful sexual relations. Her bond has been set at $50,000.
Wrobel is accused of having unlawful relations with an 18-year-old student.
Police said the investigation occurred in the 1200 block of West 10th on Saturday. The request for the investigation was made by administration.
Wrobel has resigned her position.