Food is one of the biggest contributors to climate change and biodiversity loss. What we eat, therefore is central to planetary health. The work of Poore and Nemecek (Science, June 2019), the EAT Lancet Foundation’s “Planetary Health Diet” and Metanoia’s white paper “The Carbon Footprint of School Food” (2025) shaped our understanding and led us to look closely at the food being served in school canteens and strategize about how schools could be a “place to intervene in the system,” to help catalyse a long-term societal shift to sustainable diets.
TASS worked with students at a school in HK and their caterer (Sodexo, one of the largest school catering companies in the world) to analyse 12 months of food procured for the school canteen and compare it to the EAT Lancet Diet. We found the school was consuming about 3x the amount of animal protein and dairy, about half the whole grains and 1/40th of the plant-based protein compared to the Planetary Heath Diet (by calories).
The students presented these findings to the management team at Sodexo and received a defensive response: ”students don’t like/won’t eat sustainable food”, “sustainable food is too expensive,” and “sustainable food isn’t possible at scale in Hong Kong.”
We believed these to be convenient myths and set out to disprove them and to change mindsets about what's possible with sustainable school food when done well. This led us to organise the first Sustainable School Food Summit - v1.0 of our innovation.
A Sustainable School Food Summit involves c. 100 students and staff from 20 schools (a mix of TASS members + non-members) plus several school catering companies, and local chefs specialising in sustainable food. In addition to student presentations and panel discussions about the importance and feasibility of sustainable food, the chefs are invited to design a sustainable menu item suitable for a school canteen at the same price, and serve it to attendees, explaining why it is sustainable. We also calculate the carbon footprint of each item and provide educational material about the dishes for the students to discuss during lunch.
The students vote on the dishes and - key for scaling impact - the caterers commit to offering these three sustainable dishes on the menu in all the schools they serve (many more than the 20 attending) in that city over the next year and provide us data. For reference, the three caterers in our first summit serve a total of 8 million meals every year in HK.
TASS’s modus operandi involves far more than just awareness raising. Our operating model is: connect (i.e. grow a network of schools focussed on sustainability), engage (with innovators in the local community, like the chefs), demonstrate (pilot sustainable alternatives to unsustainable practices in schools) and scale (scale out - by replicating the successful pilots throughout our network; and scale deep - by changing mindsets). The Summit is a great example of how this works in practice.
To answer this question it's important to understand a bit about TASS and how we have developed since launching in Hong Kong in Oct '22. In 3+ years we have grown to become an international network of 140 member schools in 20 countries and we have relied on membership fees to fund our work. We take a systems-thinking approach to catalysing change in the five areas that are main sources of environmental impact in most schools in developed countries - school food, school transport, school buildings and grounds, school uniforms and education for sustainability.
We held the first SSFS in HK in Apr '23 and the second in Dubai during COP28 in Dec' 23. Reflecting on our impact we saw the need to include a behaviour change component in the Sustainable School Food Summit, so we developed a parallel innovation called the Sustainable Behaviour Change Hackathon (SBCH) in collaboration with Behaven. The Hackathon takes an innovative approach to tackling sustainability challenges by equipping students with skills to identify the factors driving unsustainable behaviour and exploring how behavioural science insights can be harnessed to enable students to make sustainable choices instead of unsustainable ones. The students design and implement interventions in their school to see what works.
We held 2 SBCHs in 2024-25 in HK and Abu Dhabi with 200 attendees from 25 schools. Both included interventions in sustainable food (eg choice architecture) as well as other topics such as energy.
The next iteration of our innovation - Sustainable School Food Summit v2.0 - is designed to enhance impact by incorporating what we learned from the Sustainable Behaviour Change Hackathon, focussing purely on food-related interventions led by students in their schools.
In Phase 1, TASS collaborates with schools and students to carry out observational studies and surveys to identify barriers and enablers related to the uptake of sustainable school food.
In Phase 2, TASS hosts a one-day Sustainable School Food and Behaviour Change Hackathon. In the weeks prior to the Hackathon, students will have received 3 hours of online skills training on the use of behavioural science tools to achieve sustainability objectives. During the Hackathon, students apply a toolkit of 12 behaviour change interventions, and choose 4 that best address their chosen challenge and design a strategy for implementing those interventions in their school and pitch their solutions to their peers. The objective is to increase uptake of sustainable meals.
The Hackathon also features a keynote speech about the importance of sustainable school food, and a low-carbon school lunch tasting designed by chefs to demonstrate sustainable alternatives to existing school food options plus a range of related educational content.
In Phase 3, TASS collaborates with schools and caterers to roll-out 3-6 low-carbon meals, and support students to implement their behaviour change interventions and measure their impact.
If you are interested to bring the Sustainable School Food Summit and Hackathon to your area, please contact us at team@tass-asia.org.
We will work with you to co-organise the Summit in your city for a group of schools (whether or not they are TASS members). The ideal size for an impactful event is 10-20 schools and 100-150 students and staff. The innovation is suitable for students aged 16 and above. Some younger students have participated in the past, accompanied by a member of staff who is willing to scaffold their learning throughout the day and in the pre-event training sessions.
We require that an engaged member of staff from each school participate in all aspects including the behaviour change skills training and a pre-event briefing session. Their support will be important to ensure that the students' post-hackathon interventions are successfully implemented and reported on.
We will collaborate with the schools to identify appropriate school caterers and local sustainability chefs and brief them on the requirements and the commitments we want them to make. We will arrange the online behavioural science training for the students and handle all aspects of event management and post-hackathon follow-up.
