cram school; private tutoring school
A private after-school institution where students study to improve grades or prepare for entrance exams. Often contrasted with 塾 (a broader term) or 予備校 (focused on exam preparation for older students).
He attends a cram school after school.
学習塾の先生は、生徒一人ひとりに合わせた指導をしてくれる。
The cram school teacher provides individualized instruction for each student.