Abstract
BACKGROUND: Students’ participation in after-school activities changed during the COVID-19 pandemic. However, it remains unclear whether these changes were primarily attributable to the pandemic itself or to age-related developmental trends. This study aims to examine how activity patterns shifted during the pandemic and distinguish temporal trends related to the pandemic from normal developmental changes. METHODS: This repeated-measure cross-sectional study included 112,358 participants contributed 229,700 observations in Australia. Students who were in grades 4 to 9 between 2019 and 2022 were included. Weekly frequency of eleven activities were measured, and categorized as none, moderate, or high. Ordinal logistic regression models were used to examine the temporal trend of after-school activity participation. RESULTS: Clear temporal trends were observed across the four years: participation in social media and e-games increased over the four years, with the greatest rise in social media. Conversely, participation in sports, reading, study, friends, and clubs declined, while TV, arts, chores remained stable. These temporal trends were largely consistent across grade levels, indicating that the changes reflect pandemic-related shifts at the population level rather than age-related developmental effects. An exception was Grade 7, the first year of secondary school, which exhibited the greatest increase in social media use, and largest declines in music, arts, and reading compared to other grades. DISCUSSION: The pandemic was associated with substantial shifts in students’ activity participation, with adverse temporal trends persisting after lockdown ended. Targeted interventions are needed to support students to re-engage in beneficial activities, with special attention to groups experiencing transitioning to secondary school. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-026-26423-3.