But consider what school vacations are for. First, spring break. School in Japan starts in April. The month of March is a very busy time for school teachers, as they prepare for new students, administer entrance exams for schools that have them, and grade the scores. Therefore, schools are closed during this time.
Next is the winter vacation. This is the time of the New Year. During the New Year's holiday, there is a long-standing custom of celebrating the new year together. During this time, not only schools are closed, but also the whole country. That is why we have winter vacation.
The summer vacation was decided to be a vacation during the hot summer season because it is hard to get much done if you are forced to study. In other words, there is a reason for each long school vacation.
What about autumn? Autumn is the most pleasant season of the year. It is neither hot nor cold, making it a very comfortable season. It is the best time of the year to study. There is no reason to take the trouble to close school during such a beautiful season.
Indeed, there are many people who would like to have more time off from school, except for those who love school. But that may be a luxury. Working fathers and mothers have a hard time just getting a week off during the summer, even though they have more holidays nowadays.