Abstract
Japanese children tend to have short sleep durations, influenced by the educational environment. However, the empirical evidence of this association remains limited. This study examined the relationship between parental educational aspirations and children's sleep duration among Japanese school-aged children and investigated whether cram school attendance mediates this relationship. Using the Japanese Longitudinal Study of Children and Parents (JLSCP), a nationally representative sample was analyzed. The current study included children in grades 5-9 (ages 10-15 years) and their mothers, and revealed three key findings. First, higher parental educational aspirations were significantly associated with shorter sleep duration among junior high school students, while no such association was observed among elementary school students. Second, this relationship was partially mediated by children's attendance at cram school. Third, an inverse association between parental educational aspirations and sleep duration was evident in non-metropolitan areas. These findings suggest that parental educational aspirations reduced sleep duration in junior high school students via increased cram school attendance. The results highlight the need to revisit the role of cram schools and promote sleep hygiene education to support children's sleep, particularly in non-metropolitan areas.