If you’re a student in Japan, you might attend a juku in addition to your normal school. A juku is a private school that usually prepares students for the entrance exams to get into prestigious high schools and universities.
Students, or their parents, have to pay fees to attend a juku, which is often called a "cram school." Because attending a juku is in addition to attending regular school, classes take place in the evenings, on weekends, or during school holidays — which means a lot of school! In most juku, students get extra instruction in core academic subjects like Japanese, English, math, and science. While some juku focus on the arts or sports, the primary purpose of attending a juku is exam prep.