For environmental education about climate change issues, selecting events that are already encountered by people as teaching materials is considered effective. Consideration of changes in leafing dates over time provides a useful tool, in particular when children themselves observe plant phenology, which can be achieved using time-lapse imagery. We postulated that creating an environment where this process can be conducted at school would give children a readiness of behavior toward resolution of climate change issues. Verification of how adequately children can undertake the observations is key to establishing the methodology's effectiveness. In this research, we used time-lapse images from Shiga Heights, Nagano prefecture, Japan, that were taken once per day from 1987 to 2004; in each year from this series, we used the images taken from 27 May to 15 June, inclusive, as these were the dates during which leafing was expected. We created observation sheets and made these and the time-lapse images available for students on the Internet. As a result of our analysis of observations made by 543 students using the observation sheets, we determined that the method had sufficient adequacy for education.