In the promotion of energy efficiency in educational facilities, preschool children play an important role since simple energy-saving behaviour can be developed in early childhood. This study aimed to investigate the effects of behaviour interventions, with a particular focus on preschool children's turn-off behaviour in shared environments. The intervention tools i.e. digital game, paper-board game and visual prompt were developed for 3-6 years old children. The study took place in a preschool in which energy-efficient lighting and combined automatic and manual controls were installed. The data were collected by means of participatory observations of the children's light-off behaviour (N = 42), measurements of lighting use using data loggers, and interviews with the teachers (N = 11). The overall results point to associations between the interventions and the behaviour specifically, the visual prompts were found to have a significantly positive effect. No significant effect of the games on the behaviour could be identified however, the games were found to have the potential to promote learning about lighting and lighting use. Effects of the interventions on the long-term behaviour and energy saving remain unclear. Design improvements of the interventions are thus, needed considering other related factors (e.g. social norms, habits) together with lighting quality for young children and activities in preschool environments.CO 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).