Rising childhood obesity rates remain a pressing public health concern in Wales and across the United Kingdom. Recent evidence highlights the superior nutritional quality of school meals compared to packed lunches, underscoring the importance of promoting school meal participation to instil healthy dietary habits from an early age.

Despite the introduction of universal primary free school meals in Wales, a substantial portion of primary school children continue to opt for packed lunches, missing out on the benefits of a nutritious school meal. In response, Nesta collaborated with two pioneering councils, Caerphilly County Borough Council and Torfaen County Borough Council to pilot ‘School Meals, Count Me In Month’ (SMCMIM), a new intervention aimed at increasing uptake of universal primary free school meals in Wales, in six primary schools across Caerphilly and Torfaen. The intervention centred on setting the expectation that all pupils within a school would be eating a school meal unless their parents actively opted out by informing the council of their child’s preference for a packed lunch – shifting from the current assumption that pupils will bring a packed lunch unless their parent actively selects a school meal. This intervention set out to leverage concepts from behavioural science such as the ‘default bias’ – people's tendency to stick with a pre-set option – and the influence of ‘social norms’ in encouraging people to conform to behaviours that are common among others in their community. In four out of six schools, the switch to opt-out was accompanied by supporting activities, such as taster sessions for pupils and parents, which aimed to help build trust in the school food offer.

Key findings

• The SMCMIM intervention demonstrated potential for increasing school meal uptake. Five out of the six schools that took part in SMCMIM observed a higher increase in school meal uptake compared to non-participating schools. These schools observed between a five and 14 percentage-point larger rise in school meal uptake than non-participating schools during SMCMIM compared to a recent month.
• While SMCMIM had a moderate impact on school meal uptake, the effectiveness of the intervention was likely to have been limited by challenges in creating a default for school meals through the opt-out process. Specifically, many parents continued to send children to school with a packed lunch without formally opting out of school meals. In most cases, this did not result in their child being given a school meal instead of their packed lunch, nor in parents being engaged by the school to remind them of the opt-out process. The key barriers to more effective enforcement of the school meals default were a lack of capacity from school and catering team staff and the need for up-to-date information on allergies for all children.
• Parental, school & council catering team feedback indicated that the positive impact of SMCMIM on school meal uptake observed may have been driven by creating a strong social norm and expectation (or endorsement) for school meals from the school leadership, rather than the opt-out process making it easier to stick with a school meal instead of switching to a packed lunch.
• The impact of the taster sessions and other activities aimed at building trust in school meals to support the successful implementation of SMCMIM remains unclear despite strong support from parents for these activities – the two schools that implemented SMCMIM without taster sessions experienced both the smallest and largest increase in school meal uptake of participating schools.
• While around half of the surveyed parents said that SMCMIM would make them more likely to choose school meals in the future, a three-month post-intervention analysis of school meal uptake in Caerphilly schools revealed that in only one of the three schools that participated in SMCMIM did the increase in school meal uptake compared to non-participating schools persist considerably over this period. This suggests that SMCMIM may need to be repeated several times over the school year to obtain long-term increases in school meal uptake.

The success of this initiative was largely driven by the hard work and enthusiasm of the councils and schools we partnered with; this included school leaders vocally setting an expectation for pupils to eat a school meal. This, alongside the opportunity to increase the efficacy of the opt-out process through stricter enforcement of school meals as the default option suggests the importance of school leaders being enthusiastically brought into interventions like SMCMIM. Since addressing childhood obesity in Wales will likely require large-scale takeup of successful interventions like SMCMIM, an outstanding question remains around how to most effectively encourage and empower schools and councils across Wales to adopt interventions like this.

While leveraging behavioural change interventions like opt-out systems can nudge better dietary choices, this study suggested that these should be coupled with community engagement initiatives that give students, parents, and educators a voice to have the greatest effect.

As Wales renews its focus on curbing obesity rates, combining behavioural insights with grassroots collaboration can progressively reshape societal norms and reduce barriers to healthy eating.

This study was a collaborative effort involving Nesta, Cardiff Council, Caerphilly County Borough Council, Torfaen County Borough Council and the enthusiastic participation of headteachers, staff, pupils and parents from several primary schools across the region. We are hugely grateful to the headteachers, staff, pupils and parents of Ysgol Gymraeg Cwmbran, St David’s R.C Primary School, Garnteg Primary School, Rhiw Syr Dafydd Primary School, Blackwood Primary School and Deri Primary School who took part in these pilots. We are also indebted to Karen Spiller and Marcia Lewis (Caerphilly County Borough Council) and Tracy James (Torfaen County Borough Council). We would also like to thank the headteachers, staff, pupils and parents of Trelai and Glyncoed Primary Schools in Cardiff and Judith Gregory (Cardiff City Council) for their involvement in the design process that led to these pilots.