crammer

A crammer is a person who crams—that is, studies intensively in a short period, usually just before an exam.

In British English, crammer also refers to a school or tutoring service that prepares students for exams through intensive, focused instruction, often helping those who failed to gain admission elsewhere or need to retake tests.

He spent six months at a crammer before his university entrance exams.

The word carries a slight suggestion of last-minute desperation or mechanical learning rather than deep understanding.