Academic terms

There are two semesters in a year in most Japanese universities. The first semester begins in April and ends in September. The second semester begins in October and ends in March. A long time ago, when the first semester ended in October and the second semester began in the same month, there were two-month-long summer holidays that began about July 10th. Students used to be free from classes in the hottest season in Japan, but now they are busy at school until early August. I wonder how they are supposed to study in the classrooms in the season that is not appropriate for studying.