 The nature of the internal assessment (IA) varies by subject. There may be oral presentations (used in languages), practical work (in experimental sciences and performing arts), or written work. Internal assessment accounts for 20 to 50 percent of the mark awarded for each subject and is marked by a teacher in the school. A sample of at least five per subject at each level from a school will also be graded by a moderator appointed by the IB, in a process called external moderation of internal assessment. Based on this moderation, the grades of the whole subject from that school will change.
