EE, TOK & CAS · Extended Essay · 9 min read
Extended Essay criteria explained: what A to E reward from May 2027
What each of the five new criteria rewards, what keeps essays stuck in the middle bands, how the criteria pull on each other, and what to check before you submit.
On this page
- How is the new Extended Essay marked?
- Criterion A: what does "framework" mean?
- Criterion B: what counts as knowledge and understanding?
- Criterion C: what is a "line of argument"?
- Criterion D: why is discussion and evaluation worth the most?
- Criterion E: how is reflection marked?
- How do the criteria interact?
- A checklist before you submit
- How is this different from the old 34-mark rubric?
From the May 2027 session, the IB Extended Essay is marked out of 30 against five criteria: A Framework for the essay (6 marks), B Knowledge and understanding (6), C Analysis and line of argument (6), D Discussion and evaluation (8) and E Reflection (4). Criteria A to D are applied to the essay as a whole; criterion E is applied only to your reflective statement of up to 500 words on the Reflection and progress form (RPF). The same criteria apply in every subject and in the interdisciplinary pathway.
The descriptions below are ours, not the IB's wording, so read them next to your supervisor's copy of the guide.
You are on the old 34-mark model with different criteria. Skip to the comparison near the end, and use your supervisor's copy of the old rubric.
How is the new Extended Essay marked?
| Criterion | What it looks at | Marks |
|---|---|---|
| A Framework for the essay | Research question, research methods, structure and presentation | 6 |
| B Knowledge and understanding | Command of the subject, its terms and its sources | 6 |
| C Analysis and line of argument | Turning evidence into a connected argument that answers the question | 6 |
| D Discussion and evaluation | Weighing evidence, methods and alternative views to reach a justified judgement | 8 |
| E Reflection | Your reflective statement on the RPF only | 4 |
| Total | 30 | |
Four things about the marking matter for how you write:
- Best fit, marked positively. The examiner picks the band that describes your essay best overall and credits what is there. The top band does not demand perfection.
- The word limit is enforced by not reading. Examiners stop at 4,000 words. Anything past the limit earns nothing on any criterion, which hurts most when your conclusion sits there.
- Marks become a grade from A to E. Senior examiners set the boundaries each session using fixed grade descriptors, so boundaries can move while the standard stays put. No boundaries for the 30-mark model exist yet.
- An E fails the Diploma. You need a D or higher, and your EE grade combines with your TOK grade for up to 3 points (see how IB scoring works).
Criterion A: what does "framework" mean?
Criterion A rewards an essay that is set up to succeed: a research question focused enough to answer properly in 4,000 words, methods that can actually answer it, and a structure a reader can follow. Presentation, which used to be its own criterion, now lives here: headings, labelled tables and graphs, consistent referencing, a contents page.
What holds essays in the middle: a question that is clear but broad; methods described but not justified; a structure that follows the order you did things in rather than the order the argument needs.
Middle band"How does temperature affect enzyme activity?" with a method section that lists apparatus and steps.
Top band"How does temperature (20–60 °C) affect the rate of starch hydrolysis by fungal α-amylase, measured as 1/t, where t is the time until a sample no longer turns iodine blue-black?", with a method section that explains why 1/t is a fair measure of rate, why 5 °C intervals, and how pH and enzyme concentration were held constant.
The question is where criterion A is mostly won or lost. EE research question examples has 33 of them, across ten subjects and the interdisciplinary pathway.
Criterion B: what counts as knowledge and understanding?
Criterion B rewards accurate, relevant subject knowledge that is actually put to work: the right concepts and terms used precisely, sources that are appropriate for the question, and a clear sense of where your question sits within what is already known.
What holds essays in the middle: background that is correct but generic, textbook paragraphs that could open any essay on the topic, and terms used loosely. A "Biology" or "Economics" essay that rarely uses biology or economics is the clearest case.
Middle band"The sugar tax made people buy fewer fizzy drinks because they became more expensive."
Top band"Sales volumes fell by a smaller proportion than prices rose, which suggests demand was price-inelastic over this range. That explains why the levy raised revenue while changing consumption only modestly, and it is the key to judging the policy against its health aim."
The second version is not longer because it is padded. It uses one concept, elasticity, precisely, and that concept drives the rest of the argument.
Criterion C: what is a "line of argument"?
Criterion C rewards analysis that goes somewhere. Each section should take evidence (data, sources, quotations, mathematical results), say what it shows, and connect it to the next step, so the essay moves steadily from the research question to an answer. A reader should be able to state your argument in two sentences.
What holds essays in the middle: analysis that is correct but local. Each paragraph makes sense, but the paragraphs don't build on each other, or the essay piles up evidence and only judges it in the conclusion.
Middle band"Source A, a cabinet memo, says Britain's air defences were not ready. Source B, a newspaper, says the public wanted peace. Source C, a historian, argues Chamberlain believed Hitler could be trusted."
Top band"If military unreadiness drove the decision, the Chiefs of Staff's warnings should appear in the cabinet discussions before Munich, and they do. But they appear alongside arguments about public opinion, which weakens the claim that military advice was decisive rather than one reason among several."
A quick test: underline the first sentence of every body paragraph. If those sentences, read in order, don't make an argument, criterion C will be lower than it could be.
Criterion D: why is discussion and evaluation worth the most?
Criterion D, with 8 marks, rewards judgement: weighing evidence against other evidence, questioning your methods and sources, taking alternative interpretations seriously, and reaching a conclusion that matches the strength of your evidence, no stronger and no weaker. In the sciences that means evaluating the data and the design; in the humanities, the sources and the counter-arguments; in maths, the assumptions and limits of the model.
What holds essays in the middle: evaluation bolted on at the end as a list of limitations, and limitations so vague they could apply to any investigation.
Middle band"A limitation was human error in judging the end point. In future, more repeats would make the results more reliable."
Top band"The end point was judged by eye. At 45 °C and 50 °C the colour change took under 30 s, so a 3 s misjudgement is an uncertainty of at least 10% in the rate, larger than the difference between those two results. The data therefore show a peak around 45–50 °C but cannot say which of the two is higher; colorimeter readings at fixed times would."
The strong version uses a number, says exactly what conclusion the weakness undermines, and proposes a fix aimed at that weakness. In a humanities essay the equivalent is naming the strongest counter-argument and showing why your evidence still outweighs it, or conceding where it doesn't.
Criterion E: how is reflection marked?
Criterion E is marked on one thing only: your reflective statement on the RPF, up to 500 words. It rewards reflection on how your thinking and skills developed during the research: the decisions you made, what went wrong and what you did about it, what you would now do differently. A blank or missing RPF scores 0, and so does a statement written in a different language from the essay.
What holds statements in the middle: narration of what happened, in order, with feelings attached but no decisions explained, and generic skills ("I improved my time management") with no evidence.
Middle band"At first I found it hard to find sources, but then I found some useful ones. I learned a lot about time management and research."
Top band"My first question asked whether sanctions 'worked', and in my first session I could not say what working would look like. Choosing one measurable aim, the release of political prisoners, made the question answerable, and it is the habit I now use first: deciding what evidence would change my mind before I start reading."
Sample extracts and viva preparation are in EE reflection and the viva voce.
How do the criteria interact?
The criteria are marked separately, but they are not independent.
- A sets the ceiling for C and D. A broad question produces a descriptive essay, and description can't be analysed or evaluated in depth. Most low C and D marks start as an A problem.
- B is the fuel for C. You can't build an argument with concepts you're using loosely. Precise subject knowledge is what lets you say why the evidence points one way.
- C and D overlap but are not the same. C asks whether the argument holds together; D asks whether you have tested it. An essay can be well argued and one-sided (good C, weaker D), or full of caveats with no clear answer (some D, weak C).
- E depends on the process, not the essay. A strong essay with a rushed statement still loses up to 4 marks. You can only reflect on decisions you noticed making, so keep a research log.
A checklist before you submit
- ☐ The research question appears, word for word, in the introduction and is answered in the conclusion.
- ☐ The question is narrow enough that you have discussed it, not just described it.
- ☐ Your methods section says why, not only what.
- ☐ Every subject term is used precisely; nothing is defined once and then used loosely.
- ☐ The first sentences of your body paragraphs, read in order, make an argument.
- ☐ At least one serious counter-argument, alternative interpretation or methodological weakness is discussed where it matters, not only in the conclusion.
- ☐ Your conclusion claims no more than your evidence supports, and says what remains open.
- ☐ The essay is at or under 4,000 words, counted by the IB's rules.
- ☐ Tables, graphs and figures are labelled and referred to in the text.
- ☐ Every source is cited where it is used and listed in the bibliography in one consistent style.
- ☐ Any AI-generated material is marked, cited in the text with the prompt and date, and listed in the bibliography (see AI rules in the IB).
- ☐ The reflective statement is under 500 words, in the same language as the essay, and explains decisions rather than retelling events.
How is this different from the old 34-mark rubric?
A lot of EE advice online was written for the model assessed up to November 2026. The table maps the two so you can tell which advice still fits.
| Old model (to Nov 2026) | Marks | New model (from May 2027) | Marks |
|---|---|---|---|
| A Focus and method | 6 | A Framework for the essay (now includes structure and presentation) | 6 |
| B Knowledge and understanding | 6 | B Knowledge and understanding | 6 |
| C Critical thinking | 12 | Roughly, C Analysis and line of argument plus D Discussion and evaluation | 6 + 8 |
| D Presentation | 4 | Absorbed into A | – |
| E Engagement (on the RPPF) | 6 | E Reflection (on the RPF statement) | 4 |
| Total | 34 | Total | 30 |
The old mark allocations above are the ones commonly published in school rubrics. In practice: old advice on research questions and critical thinking still applies; advice that treats presentation as separate marks, or that tells you to write three separate RPPF reflections, does not. Old grade boundaries, which varied by session, tell you nothing about the new model. For the whole process, start with the Extended Essay guide.
Questions students ask
Which Extended Essay criterion is worth the most?
Criterion D, Discussion and evaluation, with 8 of the 30 marks. Criteria A, B and C are worth 6 each and criterion E, Reflection, is worth 4.
Is there still a presentation criterion in the EE?
Not a separate one. From May 2027, structure and presentation are judged inside criterion A, together with your research question and methods.
What are the grade boundaries for the new 30-mark EE?
None have been published yet. Senior examiners set the boundaries for each session using the EE grade descriptors, and the first ones for the 30-mark model will come after the May 2027 session. Ignore any website that prints boundaries for it now.
Does the reflective statement count towards the 4,000 words?
No. The statement on the RPF has its own limit of 500 words and is the only thing criterion E is marked on. It does not count towards the essay's 4,000.