A female teacher has been arrested in Sydney's west and charged over historical child sex offences against students, dating back 20 years.
Police detained the 47-year-old woman after visiting her home in Padstow, on Monday.
The arrest follows a 10-month investigation into alleged sex offences against a 15-year-old male student at a high school in Birrong in 1997.
"Police will allege that the boy was 15 years old at the time of the alleged offences, and the teacher was 27," NSW Police said in a statement.
Police also alleged a second 15-year-old boy at the same school was also sexually assaulted by the teacher.
The woman was charged with 16 counts of aggravated sexual assault and five counts of indecency.
She was bailed to appear in Bankstown Local Court on January 10.
Police encourage any victim of sexual assault, no matter how long ago the incident occurred to come forward. Reports can be made at any police station.