The juku
provide supplementary education for students who need additional help with
their regular school subjects, and for students who are studying for
entrance exams. Most juku courses are held during the after-school
hours or on Saturday morning.
Variations of the
juku exist in most developed countries. In Japan, however, these
institutions are far more numerous, and are attended by a far wider range
of students. This is because of the highly competitive nature of the
Japanese school system, and its heavy reliance on standardized
examinations.