Always find the food you pack to the office cold by lunchtime? A group of Secondary 3 students has come up with a product to solve that problem in an environmentally friendly way.
They developed a lunch box with a heating mechanism - an incandescent light bulb - that is powered by energy from cycling.
The five Bukit View Secondary School students, all 15 years old, said their idea would not only reduce the use of microwaves and save electricity, but also encourage people to exercise more.
"We wanted to do this project because we found that most food waste in our school comes from home-packed food being thrown away after it turns cold," said Yasmin Sim.
The team was among the winners at yesterday's finals of the Shell Stem Youth Innovation Challenge 2015, which was organised by Science Centre Singapore's unit Stem Inc and sponsored by energy company Shell in Singapore.
The competition was open to Sec 3 students from schools offering the Science, Technology, Engineering and Mathematics (Stem) Applied Learning Programme.
The teams were tasked to solve environmental issues related to food, water, energy and eco-friendly materials.
About 250 students from 31 schools took part, and the 49 teams were whittled down to the 16 finalists yesterday by Science Centre staff, engineers and Stem educators.
About 30 engineers and educators with science backgrounds mentored the teams.
Stem Inc, which runs a programme for students to be exposed to Stem industries and potential careers, had a two-day workshop for the students to learn mechanical fabrication, electronic prototyping and other skills.
Four teams were announced as winners yesterday, one each in four categories. The winning students received pens that can draw in 3D.
The Bukit View Secondary team won in the food category.
The East View Secondary team won in the water category. The students came up with a concept for an underground system that filters waste water to make it suitable for general cleaning.
A St Patrick's School team won in the energy category with an alternative to conventional clothes dryers, The team's NightDryer stores solar energy to dry clothes at night.
Students from Chestnut Drive Secondary School won in the eco-friendly materials category with a project to create biodegradable plastic files from waste food.
National Research Foundation chief executive Low Teck Seng, the guest of honour, said: "We need young people in Singapore to understand the importance of science, and to get excited about it.
"They will be important to building a country, and to making this world a more sustainable place."