Seven-year-old Emmalyn Jonatan makes it a point not to take a plastic bag when she buys a fishcake - her favourite snack during recess.
It is a habit she has picked up at her school, which gives pupils a sticker each time they avoid using disposable packaging, be it a plastic bag or straw.
"I will tell the aunty (who runs the canteen stall) that I don't want a plastic bag. I've already collected two stickers," the Primary 1 pupil at Bukit Panjang Primary School told The Straits Times excitedly.
Pupils will get a certificate of achievement once they collect 10 stickers, and stand the chance to win one of three sets of tickets to visit the S.E.A Aquarium at Sentosa.
This initiative is part of green group Zero Waste SG's new Bring Your Own Schools campaign, which was launched at the school last week, and will last a month.
So far, the initiative has been launched at one other primary school, with 11 more schools, including two secondary schools, to follow next year.
"We hope to inculcate good (bring your own) habits among the young and encourage them to reduce (the use of) plastic disposables and protect the marine environment," said Zero Waste SG's executive director, Mr Eugene Tay.
He said the programme aims to help schoolchildren find out more about plastic disposables and marine litter through assembly talks and exhibitions, and to encourage them to bring their own reusables, such as bottle, container, utensils or bag.
Mr Bucktha Seelan, Bukit Panjang Primary School's principal, said: "The kids love the stickers. Sometimes you need to incentivise as we educate, because educating kids takes a while. While a number of them are excited about the prizes, we want to spread the message beyond that."
Currently only Primary 1 and 2 pupils get to participate in the programme. Mr Seelan said he will assess the results of the programme before he considers expanding it to the other levels.
The programme is part of a wider effort to go green at the school, which already encourages its pupils to recycle newspapers, drink cans and plastic bottles. This year it also held its first flea market, where it sold old clothes contributed by its pupils and their families.
"We don't think about just educating kids, we also use kids to educate their parents," added Mr Seelan.