Objectives: This paper explores the impact of physical education (PE) lessons, focusing on children aged 6-7 years, an underrepresented age in physical activity research. Methods: 10 children wore Actigraph accelerometers recording physical activity throughout the school day (9 am until 3.10 pm), for a year. Repeated measures ANOVA analysed: type of day (days including PE and days that did not) and gender (p < 0.05). Results: Boys achieved 88% (girls 70%) of the recommended daily physical activity levels on PE days compared to 77% (girls 63%) on non-PE days. Significant differences occurred, boys more active than girls also PE days being more active than non-PE days. Conclusion: The novel findings indicate PE lessons significantly contributes to children's physical activity levels.