IB Rubrics and Marking: How Assessment Works
How IB marking works
The IB uses criterion-based assessment. Marks are awarded according to published criteria and grade descriptors, not by comparing students to each other.
The 1–7 scale
Each subject is graded 1 (lowest) to 7 (highest). Grade descriptors describe the quality of work at each level:
| Grade | Descriptor | Typical characteristics |
|---|---|---|
| 7 | Excellent | Sophisticated understanding, independent analysis, precise expression |
| 6 | Very good | Strong understanding, convincing analysis, clear structure |
| 5 | Good | Solid understanding, valid analysis, adequate expression |
| 4 | Adequate | Satisfactory knowledge, generally valid, basic structure |
| 3 | Satisfactory | Some understanding, sometimes valid, limited development |
| 2 | Poor | Limited understanding, weak development |
| 1 | Very poor | Minimal evidence of understanding |
Assessment criteria (rubrics)
Each subject has assessment criteria (rubrics) that define what is required for each mark band. For example:
- Criterion A: Knowledge and understanding
- Criterion B: Application and analysis
- Criterion C: Evaluation and synthesis
- Criterion D: Use of language / presentation
Criteria vary by subject. Marks are given per criterion, then combined.
Levels of response
For extended questions, levels of response descriptors are used. Examiners match the answer to a level (e.g. Level 1–3 or 1–5) and award marks accordingly. Higher levels require more depth, evaluation and structure.
Moderation
Internal assessments are marked by teachers and moderated by the IB. A sample of work is reviewed; if marking is off, all students in that subject/class may have marks adjusted.
Grade boundaries
Final grade boundaries are set each session using global candidate performance. They are not fixed in advance.
Tips for students
- Know the criteria—past papers and subject guides show what is rewarded
- Match the level—extended questions need developed, evaluative answers
- Address all parts—multi-part questions need all sections covered
How Tutopiya helps
Tutopiya tutors use IB criteria and rubrics to guide students. Explore IB resources or book a free trial.
Source: IB Assessment
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