IB Diploma Programme Psychology: Syllabus Guide

Course note (legacy syllabus): This guide describes IB DP Psychology for first assessment 2019, the course version now in its final teaching cycle (last examination session November 2026). A replacement course (first assessment 2027, launched February 2025) restructures the subject substantially – four contexts replace the four options, six named concepts are introduced, and the internal assessment becomes a research proposal. A companion resource for the 2027 course does not yet exist on this site.

This guide covers the full syllabus structure of IB Diploma Programme Psychology, first assessment 2019, for both Standard Level (SL) and Higher Level (HL) students. It complements the subject overview and the assessment revision notes already on the site by setting out what is actually taught – the core approaches, approaches to researching behaviour, and the four options.

Total teaching hours are 150 at SL and 240 at HL, made up of the core three approaches (90 SL / 120 HL), research methodology (20 SL / 60 HL), the chosen option or options (20 SL / 40 HL), and the internal assessment (20 hours at both levels) – both columns sum exactly: 90 + 20 + 20 + 20 = 150 at SL, and 120 + 60 + 40 + 20 = 240 at HL.

Core (90 hours SL / 120 hours HL)

• Biological approach to understanding behaviour – the relationship between the brain and behaviour; hormones and pheromones and their effects on behaviour; the relationship between genetics and behaviour; and, at HL only, the role of animal research in understanding human behaviour.
• Cognitive approach to understanding behaviour – how mental processes such as memory, perception and thinking shape behaviour.
• Sociocultural approach to understanding behaviour – how social and cultural context shapes behaviour and mental processes.

These three approaches are not alternatives to choose between – every student studies all three. Many topics within the core are deliberately revisited from more than one approach – memory, for instance, can be examined biologically (through brain structures), cognitively (through information-processing models) and socioculturally (through the influence of schema and culture on recall) – and the course expects students to recognise this rather than filing each topic under a single approach only.

Approaches to researching behaviour (20 hours SL / 60 hours HL)

Taught alongside the three content approaches above rather than as a separate block, covering the qualitative and quantitative methods psychologists use to test their ideas. This component roughly triples in hours between SL and HL (20 to 60), reflecting that Paper 3’s short-answer questions on research methodology are HL-only, tested separately from the content approaches examined in Paper 1.

Options – one at SL, two at HL (20 hours SL / 40 hours HL)

• Abnormal psychology – the definition, explanation and treatment of psychological disorders.
• Developmental psychology – how cognition, behaviour and identity change across the lifespan.
• Health psychology – the psychological factors influencing health, illness and healthcare behaviour.
• Psychology of human relationships – how relationships form, function and sometimes end.

Unlike the core, which is compulsory for everyone, your class studies only one option at SL and two options at HL. At HL, Paper 2 requires one essay question from each of the two studied options – so HL students should confirm with their teacher exactly which two options (not just one) their course has actually covered, since the SL/HL option requirement genuinely differs and the exam allocation follows that difference directly.

Internal assessment – experimental study (20 hours, both SL and HL)

A report on an experimental study designed, conducted (usually in a small group) and individually written up by the student, then evaluated with suggested modifications. It is externally moderated by IB examiners. Although the study itself is often carried out collaboratively with classmates, the write-up, analysis and evaluation must be each student’s own individual work, which is one of the more common points of confusion for students new to the assessment.

How to approach it

Because the three core approaches (biological, cognitive, sociocultural) are examined together in Paper 1 through short-answer questions plus one essay, practise moving between all three approaches on the same topic – for example, explaining memory from a biological angle and then a cognitive angle – rather than revising each approach in an isolated silo. Confirm early which single option your SL class (or which two options your HL class) actually studied, since Paper 2 is option-specific and revising an unstudied option wastes time. Approaches to researching behaviour is easy to under-revise because it has no options and feels like “just methodology”, but it is tested directly in Paper 3 through short-answer questions and is foundational to writing up the internal assessment credibly.

For every study you learn across the three core approaches, practise recalling not just its finding but its methodology and at least one genuine evaluative point – a strength or limitation of how it was conducted – since Paper 1’s essay question specifically rewards evaluation, not just accurate description of what a study found. This matters just as much for the chosen option: because only one option is studied at SL, the studies and theories within it need the same depth of evaluative preparation as the compulsory core, not a lighter treatment on the assumption that “it’s only one topic”.

The experimental study (internal assessment) is most often let down not by weak content knowledge but by insufficient ethical planning and an under-justified choice of design, so treat the research-methodology content from “approaches to researching behaviour” as directly applicable to your own IA rather than as separate exam content – students who can explain why they chose their specific experimental design, and what its ethical considerations were, in the same rigorous way they would evaluate a published study tend to score more highly than those who describe their procedure without justifying it.

Because the option content roughly doubles in hours between SL (20) and HL (40), HL students should not assume their second option can be covered at the same depth in less time simply because it was added later in the course – the syllabus allocates genuinely equal teaching time to both of an HL student’s two options, and Paper 2 examines them with equal weight.

Official syllabus

International Baccalaureate Organization, Diploma Programme Subject Brief – Individuals and Societies: Psychology, first assessment 2019, © 2018.