Anaheim resident Michele Lynn Johnson, 45, is a math teacher at Brea Olinda High School in Brea.
The alleged victim reportedly told his father he was having sex with Johnson, his teacher. The father then notified police.
Johnson was questioned at her house in Anaheim Wednesday and subsequently arrested on suspicion of unlawful sexual intercourse with a minor. She was released after posting $20,000 bail.
Johnson has been a teacher at Brea Olinda for eight years. She was placed on administrative leave during a police investigation. If charges are filed, the school's superintendent said Johnson will be placed on unpaid leave.
Detectives say Johnson is married with two children.
The Brea Police Department and the Brea Olinda Unified School District are working together to be sure Johnson has no contact with students. Detectives are actively investigating the possibility there may be other victims. Anyone with additional information is asked to call Detective Debbie Stark at (714) 990-7638.