This study will assess the effect of a low sugar food and drink policy on a range of important child health and learning outcomes. We will measure BMI z-score, absenteeism, truancy, and student achievement of primary school students from a school that has had ‘water only’ and ‘healthy kai’ policies in place for more than ten years, and compare these to measurements taken from the two nearest schools with a similar demographic profile but no such nutrition policy. These schools are located in a socioeconomically disadvantaged area of Auckland which is decile 1 ranked. They each have a student population that are comprised of ≥ 80% Pasifika/Māori. A recent study has already shown that this school (that has had ‘water only’ and ‘healthy kai’ policy for 10+ years) has significantly better oral health, with fewer diseased, missing, or filled teeth (DMFT) compared to the eight surrounding schools.