A series of articles by Prof. Yamaguchi in the daily Nikkei

A series of articles on preschool education as an investment in human resources by Associate Professor Shintaro Yamaguchi has been published in the "Daily Nikkei" as part of the section "Easy to Understand Economics". The series consisted of seven sequels, which the newspaper ran on weekdays from July 29 to August 5.
In it Prof. Yamaguchi introduces to the readers important studies carried out in the West which show that preschool education not only makes children happy but has a huge economic effect in that it is linked with increased employment and income among adults and less reliance on social welfare. It also reduces the future burden on society through better socialization of children (fostering of patience and resilience) and the reduction of aggressive behavior and crime.
However, Prof. Yamaguchi also warns that there are studies that indicate the existence of unintended negative consequences of preschool education, since children spending time in kindergartens and day care centers lose quality one-on-one time with their parents, which is especially detrimental for newborns. Another, indirect negative effect is that, since parents who have enrolled their children in kindergarten tend to work more and thus experience work-related stress, often taking their frustrations out on children. Prof. Yamaguchi goes on to point out that positive effects observed in the US and elsewhere in the West in the past are not necessarily applicable Japan because its socio-economic conditions are different. Nonetheless, an analysis by Prof. Yamaguchi and his team of the data collected by "The Longitudinal Survey of Children Born in the 21st Century", which follows approximately 80,000 Japanese children from their birth, has shown that positive effects of preschool education exist in Japan too - they were observed in increased language ability and the improvement of behavior among children, i.e., less hyperactivity and aggressiveness (regardless of the socioeconomic layer), as well as in the increased satisfaction due to a reduction in childrearing stress among mothers from lower income families.
Furthermore, the professor notes that the recent increase in day care facilities in Japan has had a certain effect on the increase of mothers' labor force participation rate, but warns that the soon-to-be-implemented new policy, which will partially make the utilization of kindergarten and daycare services free of charge, may aggravate the problem of the lack of facilities and lengthen the waiting lists for enrolment in day care centers. In order to deal with that a further increase in daycare centers will be needed, which may compromise the quality of care, which is why the professor is calling for increased attention by qualified experts to the quality of preschool child care.
Finally, he also suggests that one way of dealing with the problem of the lack of awareness or information among parents regarding the benefits of preschool education might be lowering the age for mandatory education.