IB Psychology HL vs SL: where the 22-mark paper actually diverges

IB Psychology is the systematic, scientific study of behaviour and mental processes, taught as an Individuals and Societies subject within the IB Diploma. Across both Higher and Standard Level, the course trains candidates to read original research, evaluate competing approaches, and write under timed conditions on a paper that rewards structure as much as content. This article focuses on a narrow but decisive slice of the syllabus: how to plan an extended-response question on Paper 1 Section B so that the rubric descriptors are met in the order examiners actually read them. Most candidates reading this who are sitting the diploma in the coming sessions will recognise the moment when a 22-mark question looks terrifying, then look forgiving, and then look terrifying again. The goal here is to replace that oscillation with a repeatable planning method.

Why the Paper 1 ERQ is graded on a sentence-shape, not a paragraph count

The single most common mistake I see in IB Psychology Paper 1 Section B is paragraph inflation. Candidates write four long paragraphs, breathe, and hope the rubric will average out. It does not. Extended-response questions on this paper are graded on a sentence-shape: each top-band descriptor maps to a specific sentence, and the candidate's job is to place the right sentence at the right point in the answer. A 22-mark question typically allocates marks across four or five descriptors, and at Higher Level the descriptors stack vertically rather than in parallel, meaning that a weak second sentence can cap the mark on the first sentence regardless of how well the first sentence was written.

For Standard Level, the same logic applies but the descriptors run in parallel bands of 3 to 4 marks each, so a candidate can still rescue a weak paragraph if another paragraph is strong. The shift to vertical marking at Higher Level is the cleanest signal that the rubric is a hierarchy, not a list. In practice, this means a candidate who produces one excellent paragraph and three mediocre ones on an HL ERQ will usually score lower than a candidate who produces four solid paragraphs, even when the total word count is similar.

Three rules follow directly from this observation. First, plan in sentences, not paragraphs, before any prose is written. Second, write the sentence that scores the highest-weighted descriptor first, because if time runs short, that sentence will already be on the page. Third, never repeat a descriptor's vocabulary without changing the verb. Examiners read for verb movement: a candidate who only describes will be capped, no matter how accurate the description is.

A common pitfall at this stage is treating the ERQ as a long short-answer question. The SAQ and the ERQ on Paper 1 share vocabulary, but they do not share shape. An SAQ has three discrete marking points, and each can be attempted independently. An ERQ has integrated descriptors, and the second descriptor often requires the candidate to extend the first. Treating an ERQ as a stretched SAQ is the fastest way to land in the middle band.

The sentence-by-sentence planning method

Before writing, the candidate should underline the command term, count the descriptors the rubric is likely to use, and write a single sentence next to each descriptor. The writing phase becomes transcription, not invention. For a 22-mark ERQ on, for example, cognitive processing, the descriptor map will typically include a definition, a study reference, a study detail, an evaluation in the same domain, and a counter-evaluation. The plan is five sentences. The candidate writes five sentences, then expands each into a paragraph of two or three further sentences. The total answer is closer to 15 to 18 sentences, not 30.

Reading the IB Psychology command term before reading the stimulus

Candidates who score in the top band on IB Psychology Paper 1 ERQs read the command term twice and the stimulus once. The command term carries the verb that determines the descriptor, and the stimulus carries the content that the verb acts on. Reading them in the opposite order leads to a paragraph of content followed by an awkward verb tacked on at the end, which is the signature of a band 3 answer.

The command terms that appear most often on Paper 1 ERQs are 'discuss', 'evaluate', 'to what extent', and 'compare and contrast'. Each one has a different sentence-shape:

• Discuss expects a balanced argument, usually two supporting statements and two opposing statements, with a conclusion sentence that names the direction of the argument rather than the topic.
• Evaluate expects a strength and a limitation, applied to the same study or theory, with a sentence that judges the overall weight of the evidence.
• To what extent expects a directional claim, two reasons for the claim, one reason against, and a closing sentence that re-states the direction with a qualifier such as 'in some contexts' or 'when measured by X'.
• Compare and contrast expects two approaches, a similarity sentence, a difference sentence, and a sentence that names the implication of the difference for the overall argument.

Notice that none of these shapes end with a definition. A candidate who begins a 'discuss' ERQ with a definition has already wasted the first sentence on a descriptor worth at most one mark. Re-arranging the opening so that the definition supports the first argument sentence is a small change that returns a whole descriptor's worth of marks across a paper.

How this changes the way a stimulus is read

Once the command term is mapped to a sentence-shape, the stimulus becomes a content bank, not a writing prompt. The candidate highlights phrases that match each planned sentence, not phrases that sound interesting. In my experience this is the single most reliable way to convert reading time into writing time: the highlighting takes about 90 seconds, and it saves about 4 minutes of paragraph planning later. Across a 90-minute paper, that 4 minutes is the difference between finishing the third ERQ and abandoning it.

Mapping the 22-mark IB Psychology ERQ rubric before any prose is written

The IB Psychology extended-response rubric is not a checklist. It is a ladder. At Higher Level, the ladder usually has five rungs: knowledge and understanding of the topic, knowledge and understanding of the research, application of the research to the question, evaluation, and a synthesis sentence. At Standard Level, the ladder usually has four rungs, with the synthesis folded into the evaluation. A candidate who has not drawn the ladder before writing will end up writing parallel paragraphs, which is the structural shape of a band 3 answer.

Drawing the ladder takes about 3 minutes. The candidate should write the five rung labels down the left margin of the planning area, then underline which part of the stimulus will satisfy each rung. For an HL ERQ, a typical ladder might look like the following:

1. Rung 1: Topic definition, drawn from the syllabus glossary, not from a generic dictionary.
2. Rung 2: Study reference, named, dated, and methodologically placed (laboratory experiment, case study, observation, and so on).
3. Rung 3: Study detail that directly answers the command term, not a peripheral detail that shows the candidate has read the study.
4. Rung 4: Evaluation, restricted to one strength and one limitation, applied to the study, not to the topic in general.
5. Rung 5: Synthesis sentence, usually about 20 to 30 words, that names the implication of the evaluation for the original argument.

The synthesis sentence is the rung that most candidates skip, and it is the rung that lifts an answer from band 4 to band 5. The synthesis sentence does not introduce new evidence. It draws a conclusion from the evaluation already on the page. A common pitfall here is to write a generic conclusion that could be lifted from any ERQ on the topic. Examiners read for topical specificity in the synthesis sentence, not for elegance.

A worked example of a 22-mark ladder on a cognitive ERQ

Take an ERQ that asks candidates to discuss the working memory model as an explanation for short-term recall. The ladder for an HL candidate might run: definition of the working memory model, reference to Baddeley and Hitch, the phonological loop detail, a strength (parsimony) and a limitation (lack of neural evidence) applied to the model, and a synthesis sentence on whether parsimony compensates for the lack of neural evidence in classroom settings. The point is not the content; the point is the rung order. A candidate who reverses rungs 4 and 5 will end up with a paragraph of evaluation followed by a sentence of synthesis, which is harder to write and easier to cap.

Why study detail is the discriminator between band 4 and band 5 on IB Psychology ERQs

Across the IB Psychology mark schemes I have studied, the descriptor that decides band 4 against band 5 on an ERQ is almost always study detail, not evaluation. Evaluation is taught explicitly in classroom preparation programmes, and most candidates reach the same generic strengths and limitations: small sample, cultural bias, low ecological validity. Examiners have read these strengths and limitations hundreds of times. Study detail, on the other hand, is specific to the question and specific to the study, and a candidate who writes a study detail that the examiner has not seen in the previous ten scripts will pull marks.

What counts as study detail? It is a sentence that names a methodological choice, a participant group, a stimulus, a measurement, or a finding, and then connects that detail to the question's command term. A candidate writing about the working memory model might name the digit-span task used by Baddeley and Hitch, the length of the lists, and the pattern of errors, and then state that the pattern of errors is consistent with a phonological loop rather than a unitary short-term store. That is a study detail. A candidate writing 'Baddeley and Hitch conducted an experiment that supported the model' is not writing a study detail; the candidate is writing a study reference.

The shift from reference to detail is mostly a sentence-shape change. The reference sentence is 'X (year) found Y'. The detail sentence is 'X (year) used Z to measure W, and found that Y was greater when Z was varied'. The detail sentence carries the same information and one more variable. Across a 22-mark ERQ, two detail sentences will usually lift the answer by one band.

Where candidates lose the study detail marks

The most common pitfall at this stage is to over-claim. A candidate who writes 'Baddeley and Hitch used fMRI to identify the phonological loop' is fabricating a study detail, and the fabrication will be read against the mark scheme, which lists the actual method. Fabrication is one of the few ways to lose a band on an ERQ; examiners do not give credit for confident invention. A safer alternative is to write a study detail that the candidate genuinely remembers and to anchor it to the syllabus glossary rather than to a secondary source.

Time budgeting on IB Psychology Paper 1: the 90-second rule for ERQ planning

Candidates who run out of time on IB Psychology Paper 1 usually do so on the second ERQ, not the first. The first ERQ receives the benefit of fresh attention, and the third ERQ receives the benefit of fatigue management. The second ERQ is where the candidate's planning method is tested for the first time under pressure, and it is where the paper is most often abandoned. A simple time rule prevents this: spend 90 seconds planning each ERQ, regardless of how clear the question looks.

Why 90 seconds? Because the planning method described above (command term, ladder, study detail map, synthesis sentence) has four steps, and each step takes about 20 to 25 seconds when the candidate is practised. A 90-second budget is enough for all four steps and not enough for the candidate to second-guess the plan. The writing phase then takes about 18 to 20 minutes per ERQ, leaving about 5 minutes at the end of the paper for review.

A useful framing is that the 90 seconds are spent buying the next 20 minutes. The candidate is not planning for the pleasure of planning; the candidate is buying time at the writing stage by removing the moments of invention that usually eat the clock. Across a two-hour paper, this is the difference between a candidate who finishes the third ERQ and a candidate who writes three quarters of it.

A table of time budgets across the IB Psychology paper structure

The following table maps approximate time budgets across the IB Psychology written papers for a candidate aiming at a band 5 to band 6. SL and HL candidates share the same per-question budget; the difference is the number of questions answered.

These figures assume a 90-second planning budget on each ERQ and a 60-second planning budget on each SAQ. A candidate who exceeds the planning budget on one question must reclaim the time from a later question, not from the review block.

The IB Psychology internal assessment: where the SAQ discipline transfers

The Paper 1 ERQ discipline transfers directly to the IB Psychology internal assessment, which is a replication study report graded on four criteria: exploration, design, analysis, and evaluation. Each criterion has a band descriptor, and each band descriptor is a sentence-shape, not a paragraph count. The replication report is graded on whether the candidate placed the right sentence at the right point in each section, in the same way the ERQ is graded on whether the candidate placed the right sentence at the right point in the answer.

For the exploration criterion, the candidate's sentence must include a research question that is operationalised, a hypothesis that follows from the research question, and a directionally clear prediction. For the design criterion, the candidate's sentence must include a participant description, a sampling justification, a controlled variable, and an ethical consideration. For the analysis criterion, the candidate's sentence must include a descriptive statistic and an inferential statistic, both applied to the data set, and a decision about the hypothesis. For the evaluation criterion, the candidate's sentence must include a strength and a limitation, both tied to the methodology rather than to the topic.

The internal assessment is also where the candidate's vocabulary discipline is tested. A candidate who writes 'the study was reliable' without operationalising reliability will be capped at band 2 on the evaluation criterion. A candidate who writes 'the inter-rater reliability of the observation schedule was high, which suggests that the operationalisation of aggression was consistent across coders' is writing an evaluation sentence at band 4 or band 5.

Common pitfalls and how to avoid them

Across both Paper 1 ERQs and the internal assessment, the same six pitfalls cap marks at band 3 or band 4. The list below names each pitfall and the sentence-shape change that resolves it.

• Definition-first openings. Begin with the argument, not the definition. A definition belongs inside the first argument sentence as a clause, not as a standalone paragraph.
• Evaluation without application. A generic strength or limitation is band 3. The same strength or limitation, applied to the study's specific method, is band 5.
• Synthesis that introduces new evidence. The synthesis sentence is a conclusion from the evaluation already on the page, not a new study reference.
• Study reference without study detail. A reference is 'X (year) found Y'. A detail adds a methodological variable. Aim for two detail sentences per ERQ.
• Command term drift. Writing 'discuss' sentences inside a 'to what extent' answer. Match the verb to the command term on the question paper, not to the candidate's preferred style.
• Time spent on the third ERQ at the expense of the second. The second ERQ is the paper's pressure point. Plan it in 90 seconds, even if the candidate knows the content cold.

How IB Psychology scoring converts a 22-mark ERQ into a band 1 to 7 grade

IB Psychology marks are converted to a band 1 to 7 grade by way of a boundary scale that is set after each examination session. The conversion is not strictly proportional: a candidate who scores 70 percent on a paper does not always land at band 7, because the boundary depends on the cohort's overall performance on that paper. What a candidate can control is the raw mark, and a 22-mark ERQ is worth roughly a quarter of the raw mark on Paper 1, which makes it the single most leveraged question on the paper.

For a candidate aiming at a 7, the practical interpretation is that the ERQ must score in the top two bands of its rubric, and the SAQs must score in the top band. A candidate who scores top band on the ERQs but mid band on the SAQs will land at 6. A candidate who scores top band on the SAQs but mid band on the ERQs will also land at 6. The two sections are not interchangeable; they pull the final grade in different directions, and the ERQ has more weight.

A second observation worth noting is that the boundary scale is steeper at the top than at the bottom. Moving from band 4 to band 5 on the ERQ often requires one additional descriptor, while moving from band 5 to band 6 requires a sentence-shape change rather than an additional descriptor. The implication for preparation is that a candidate who is already in band 4 should focus on the synthesis sentence, not on adding more evaluation.

How a one-to-one tutor can isolate the candidate's ERQ band

A preparation strategy that works in practice is to write a single 22-mark ERQ under timed conditions, mark it against the official rubric, and then identify which rung of the ladder is weakest. The candidate then writes two more ERQs that target the weak rung specifically, not the strong rungs. This is a more efficient use of preparation time than writing ten ERQs across the syllabus, because the weak rung is usually a sentence-shape problem, not a content problem. Most candidates reading this who have written ERQs under timed conditions will recognise the pattern: the same rung, the same descriptor, the same capped mark, three papers in a row.

Pulling the threads together: a 25-minute IB Psychology ERQ routine

The full routine, end to end, fits inside the 25 minutes recommended above and can be rehearsed in a single sitting. The candidate should plan to spend 90 seconds on command-term reading and stimulus highlighting, 60 seconds on ladder drawing, 2 minutes on the study detail map, and the remaining time on writing the answer in five paragraphs, one per rung. The synthesis sentence is written last, after the evaluation paragraph, and is not allowed to exceed 30 words.

Two final tactical notes. First, the candidate should number the paragraphs in the planning area, not in the final answer. Numbered paragraphs in the final answer read as a list, not as an argument, and the rubric is graded on argument shape. Second, the candidate should not read the question paper's stimulus as a writing prompt. The stimulus is a content bank; the command term is the writing prompt. Most candidates reading this will recognise the moment when the stimulus looks interesting and the answer starts to drift toward the stimulus and away from the command term. The 90-second planning budget is the structural defence against that drift.

For a candidate preparing for the diploma in a single sitting, the routine above is enough to convert a band 4 ERQ into a band 5 ERQ. For a candidate aiming at band 7, the routine is necessary but not sufficient; the candidate must also rehearse the synthesis sentence until it can be written in 30 words without a second draft. That is a writing habit, not a planning habit, and it is built across ten timed essays, not across a single one.

Conclusion and next steps

IB Psychology Paper 1 Section B rewards candidates who plan in sentence-shapes, match command terms to verb movement, and protect a 90-second planning budget on every extended-response question. The internal assessment applies the same sentence-shape discipline, and the conversion from raw mark to band 1 to 7 grade is most sensitive to ERQ performance. A candidate who has read this far and is still writing ERQs as long paragraphs has the next two months to convert the habit. IB Courses' one-to-one IB Psychology programme analyses each candidate's ERQ script against the official rubric, isolates the weakest rung of the ladder, and turns a 7 target into a 25-minute paper routine built on sentence-shape planning.

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