This article compares two learning units developed by elementary schools in Japan and Hong Kong to engage students in learning about and taking action to promote social cohesion through community participation. We choose two similar learning units for comparison, both focusing on issues related to older people in the community. Based on our analysis of their activity design and practices, we outline five directions for educational practitioners interested in promoting community participation for social cohesion in Hong Kong and Japan: practicing service-learning, promoting social cohesion, learning authentic skills, integrating community participation into the curriculum, and helping students become active members of society. This paper argues for the importance of developing such learning units to foster young citizens' contribution to their communities in post-industrial, ageing societies. Copyright © 2023 OpenED Network.