Singapore, Dec. 8 -- For some children, the humble bookshop at school presents temptations of a budgetary kind.

Youngsters who are learning to manage their pocket money sometimes buy stationery or knick-knacks, rather than a plate of food in the canteen.

Take Ms Diana Ooi, who earlier this year learnt that her eight-year-old son Leighton Kuah had been saving up to buy two keychains at the school bookshop - one for himself and another for his sister Leanne, 13.

"When I asked what he ate at recess, his facial expression changed. He had also been extremely diligent about taking food from home (to school)," said Ms Ooi, 38, who heads the start-up division for business banking at OCBC Bank.

For Leighton, the incident was a lesson in bein...