A 42-year-old teacher was jailed for six months on Wednesday for committing indecent acts on a 13-year-old boy who was studying in the same school.

She had pleaded guilty on Feb 5 to kissing him on the lips and giving him love bites on his neck and shoulder.

In passing sentence, District Judge Ng Peng Hong noted that the case involved "the sexual grooming of a young victim by a teacher" and said that a jail sentence was appropriate as it is the public policy to protect the young and vulnerable.

He also said that the teacher had breached her duty to the school and to the boy's parents. Judge Ng noted the wide age disparity of 29 years between the boy and the teacher as an aggravating factor.

The teacher and the boy had met in early 2012 when the boy was in Primary 6. He was in the same football team as the teacher's son. She also taught his two sisters Malay dance at the school, which is in the west of Singapore. The boy and his sisters became friendly with the teacher and her four children, and he would also chat with her on Facebook.

On four occasions from Oct 22 and Nov 13, 2012, he played truant to join her on trips to the movies, Sentosa and the Botanic Gardens. It was in the parks where she would kiss him and give him love bites. It was after their trip to the Botanic Gardens that the mother spotted the love bites. The boy revealed to her his relationship with the teacher.

The parents informed the school and got their son to lodge a police report. The teacher was suspended and charged in court.

Defence counsel Peter Fernando had asked the court to consider imposing a fine or placing the teacher on probation. He said his client had been suffering from a major depressive disorder but she is now coping well with treatment. However Judge Ng said that there was no psychiatric evidence of "a causal link" between her depression and her committing the offences.

The woman, who had been teaching the Malay language for 11 years, could have been jailed for up to five years or fined up to $10,000 fine, or sentenced to both. She cannot be named as it could lead to the identification of the minor.