SINGAPORE - A former chemistry teacher was jailed for six weeks on Thursday for stealing $2,050 from a student who had left her bag unattended in the classroom.

Sandridge Ong Wee Koe, 37, was teaching at St Francis Methodist School in Upper Bukit Timah Road when he stole from 17-year-old Wang Juan on Oct 16 last year. He has since made full restitution.

A second charge of stealing $1,300 from another student that day was taken into consideration. No restitution has been made as the student cannot be contacted.

The court heard that Ong had finished teaching his last class at about 2.40pm that day when he went to a classroom. The lights were turned off and no one was around.

He saw some bags which were unattended.

He opened Wang's bag and took $2,050 from her wallet. Wang, who had left for a physical education lesson, had intended to use the money to pay her school fees.

Ong, who was then in financial difficulties, had credit card debts of $6,000 to $7,000. He also owed a licensed moneylender $3,000 and used $1,200 of the stolen sum to repay the moneylender. He spent the rest on transport and daily expenses.

Ong's lawyer Louis Joseph said in his mitigation plea that his client is highly educated with commendable achievements.

The Nanyang Technological University graduate and National Institute of Education-trained teacher is remorseful and contrite, and fully co-operated with the authorities, he said.

Psychiatrist Y.C. Lim has said that Ong's behaviour was akin to a "depersonalization-derealization experience", a disorder involving being outside oneself, observing one's actions, feelings, thoughts and self from a distance as though watching a movie.

Deputy Public Prosecutor Patrick Tay cited two aggravating factors - Ong's abuse of his position of trust and responsibility as a teacher and the large sums stolen.

He said an Institute of Mental Health psychiatric report states that Ong did not suffer from any mental disorder at the material time. Dr Lim also does not dispute this and also concludes that Ong was not of unsound mind then, he added.

Ong could have been jailed for up to seven years and fined for theft in dwelling.