Writing essays for IB Psychology is one of the most overwhelming tasks IBDP students face. The Extended Response Question (ERQ) — the 22-mark essay — becomes a painstaking exercise for one simple reason: most students were never shown how to actually approach a 22-marker.
There is a structured format you should follow every time. Before we get into it, know the brief: the ERQ is a comprehensive analytical essay worth 22 marks, expected to run 800–1,000 words across six paragraphs of roughly 150 words each. Master the structure, and the marks stop feeling random.
The structure: introduction, body, conclusion
At its core the ERQ is simple — introduction, body, conclusion. The skill is in what goes inside each.
Introduction
Open with a hook or anchor concept relevant to the question. Then define and unpack every keyword and concept the question turns on. Don't leave those definitions in the introduction — weave them through the essay as the fundamentals underpinning your argument. Keep the register formal: never write in the first person ("I think…"); exemplify the topic in an academic tone.
Body
The body carries the research. For each study or theory you bring in, cover the essential understanding, aims, participants, method and tools, procedure, results, and conclusion. Crucially, highlight the theory that the experiment or case study captures — examiners reward you for showing what the research demonstrates, not just describing what happened.
Then evaluate. A strong ERQ tests the underlying theory against precise determinants: is it testable, supported by empirical evidence, applicable, valid, built on sound assumptions, free of bias, and predictive? Your evaluation must be driven by evidence — and you need at least two pieces of supporting evidence and counter-evidence to do it properly.
Conclusion
Consolidate. Summarise the essay by striking a clear balance between claims and counterclaims, each anchored in the research evidence you presented.
Moving up the mark bands
The IB Psychology ERQ is marked on five assessment criteria totalling 22 marks. Knowing where the marks sit tells you where to spend your words.
| Criterion | Marks | What it rewards |
|---|---|---|
| A · Focus on the question | 2 | Staying tightly on the relevant aspects of the theory the question asks about. |
| B · Knowledge & understanding | 6 | Accurate, precise use of the relevant keywords, definitions and concepts. |
| C · Use of research | 6 | Supporting your answer with substantial evidence — a minimum of two claims and counterclaims. |
| D · Critical thinking | 6 | Research and methodology, triangulation across qualitative data, assumptions and biases, alternative theories, contradictory evidence, and areas of uncertainty. |
| E · Clarity & organisation | 2 | A coherent, organised, seamless flow of thought. |
A and E look like easy 2-markers — but E in particular demands real planning to earn. The bulk of the essay (B, C, D = 18 marks) lives in the body, which is why the body must do the heavy lifting.
Don't ignore the command terms
The command term tells you exactly what the examiner wants. The four that dominate ERQ Psychology:
- Discuss — offer a considered, balanced review covering a range of arguments, factors or hypotheses. Present conclusions clearly and back them with relevant evidence.
- Evaluate — assess the strengths and limitations; make judgments about ideas, works, solutions or methods against selected criteria.
- To what extent — weigh strengths and limitations, supported by substantial evidence.
- Compare and contrast — give an account of the similarities and differences between two or more items, referring to all of them throughout.
Misreading the command term is one of the fastest ways to cap your own mark — a "to what extent" answered as a description will never reach the top band.
The bottom line
Practise writing ERQs in this exact format — structured introduction, evidence-driven body with two-sided evaluation, balanced conclusion, and a constant eye on the command term. The students who internalise the structure are the ones who walk into the exam aiming for a perfect 22.
Want examiner feedback on your ERQ before the exam?
We run a free 30-minute ERQ review with one of our IB Psychology examiners. Bring a past essay and the question you're stuck on — we'll show you, criterion by criterion, exactly where the marks are slipping and how to recover them.
— Dr Sukanya Pal