Abstract: We developed teaching materials focusing on diurnal variation of urban heat island (UHI) intensity using data from the Japan Meteorological Agency and practiced lessons to high school students. A graph of daily temperature variations in urban and suburban areas helped the students comprehend the UHI characteristics, which are more pronounced in the nighttime than in the daytime. Furthermore, the following two points were effective for enabling the students to learn about the daily variation in the UHI intensity, which is caused by the difference in temperature drop between urban and suburban areas in the afternoon and evening:(1) learning the differences in thermal properties between urban and suburban areas and (2) learning about radiative cooling, which is apparent at nighttime. In addition, to understand (1), it was effective to compare the differences in land cover and surface temperature between urban and suburban areas using thermographic images.