A secondary school teacher became romantically involved with her 15-year-old student and told him to perform sexual acts on her.
On one occasion, she recorded a video of herself and the minor in bed in a Geylang hotel room.
That was three years ago.
Now 29, she was sentenced yesterday by District Judge Christopher Tan to two years and nine months in jail.
The woman, who taught in a school in the north-western part of Singapore, pleaded guilty to two counts each of offences under the Children and Young Persons Act, as well as sexual penetration acts involving a minor.
She cannot be named as a gag order has been imposed to protect the teenager's identity.
The woman, who is no longer teaching in any school, has been suspended since February 2017.
The woman and the boy met in 2014 when she taught his class mathematics.
She stopped teaching his class in 2016.
However, in March that year, they became close after she accompanied his uniformed group on a camping trip.
In late November 2016, the boy lied to his mother that he was attending a camp with his uniformed group, when he was actually with the teacher at the Super 8 Hotel in Geylang from Nov 28 to Dec 2.
The mother discovered the relationship when she found letters folded into heart shapes in her son's bag.
She also found motor vehicle registration papers in the teacher's name, a condominium access card and a car key. The teacher had asked the boy to start her car while she was on holiday.
The boy's mother, who is 46, inferred from the documents that the teacher was about 11 years older than her son. Soon after, the boy asked his mother if she would consider marrying someone 11 years older than her.
Sensing something was amiss, the mother alerted the school. The teacher was arrested after the police interviewed her on Feb 16, 2017.
The Ministry of Education, replying to The Straits Times, said it "will not hesitate to take disciplinary action against those who fail to adhere to (its) standards of conduct and discipline, including dismissal from service".
The teacher is out on bail of $15,000 and has been ordered to surrender herself at the State Courts on June 24 to begin her jail term.