The IB Internal Assessment (IA) is a coursework component that forms part of every subject in the IB Diploma Programme (IBDP). It is internally assessed by your school teacher against published IB criteria and then externally moderated by an IB examiner. Every IBDP subject includes an IA component, though the format and grade weighting vary by subject group.
What Is the IB Internal Assessment?
The Internal Assessment (IA) is an assessed piece of work that sits alongside your written examinations as a core component of every IB Diploma Programme (IBDP) subject grade.
Where your examinations test timed recall and analytical writing under pressure, the IA is designed to assess skills, methods, and capabilities that formal examinations cannot capture — original investigation, oral communication, mathematical exploration, and personal creative or analytical inquiry, depending on your subject.
Every student in the IBDP completes an IA for each of their six subjects. The process is internally assessed: your subject teacher marks your IA using the IB’s published assessment criteria.
A sample of marked IAs from your school is then externally moderated by a certified IB examiner, who checks that your teacher’s marking is consistent with the IB’s expected standards across schools worldwide.
This two-stage process — internal marking followed by external moderation — is one of the key differences between the IA and your examinations, which are marked exclusively by IB examiners.
The IA contributes to your final subject grade alongside your written examination scores. The exact contribution varies by subject — for most subjects, the IA accounts for approximately 20–30% of the final grade.
For some Arts subjects, it can be significantly higher. Because your IA is assessed by a teacher you know, in conditions you can plan for, and on a topic you have chosen, it represents one of the components students can prepare for most strategically.
How the IB Internal Assessment Is Assessed
Understanding exactly how your IA is marked is one of the most practical steps you can take towards a strong score. The assessment process has two distinct stages, and the distinction between them matters.
Stage 1 — Internal marking by your teacher. Your subject teacher marks your completed IA using the IB’s published subject-specific assessment criteria. Every IBDP subject has its own criteria document, and your teacher applies these criteria to produce a total mark out of the available points. Your teacher is not inventing their own standards; they are applying the IB’s published rubric to your work.
Stage 2 — External moderation by a certified IB examiner. The IB selects a sample of internally marked IAs from each school and sends them to a certified IB examiners for moderation. The examiner reviews the teacher’s marking against the IB’s expected standards and checks for consistency. If the examiner finds that the teacher has marked systematically higher or lower than the IB standard, all students’ marks from that school are adjusted accordingly. This means your final IA mark reflects both your teacher’s assessment and the IB’s external validation of that assessment.
Our examiner team draws on moderation experience from May and November sessions. When they advise students on IA development, they draw directly on what they observe during moderation: which approaches earn marks, which approaches lose them, and where the gap between a student’s effort and their score most commonly appears.
IB Internal Assessment by Subject
Every IBDP subject group has its own IA format, tailored to the skills and methods that define that discipline. The table below covers all six subject groups, the IA format used in each, and what each assessment involves. If you are selecting DP subjects or planning your IA approach, use this as your reference point.
Subject Group | Key DP Subjects | IA Format | Brief Description |
Group 1 — Language & Literature | English Language & Literature (HL/SL) | Individual Oral (IO) | A 15-minute oral examination in which the student analyses extracts from their chosen literary and non-literary works. Internally assessed by the teacher; externally moderated by an IB examiner. |
Group 2 — Language Acquisition | Language B (HL/SL); ab initio | Individual Oral (IO) | A structured oral activity assessing conversational fluency and analytical language skills. Teacher-assessed and externally moderated. |
Group 3 — Individuals & Societies: History | History (HL/SL) | Historical Investigation | A 2,200-word written investigation into a historical question of the student’s choice. Includes source evaluation and historical analysis. |
Group 3 — Individuals & Societies: Economics | Economics (HL/SL) | Portfolio of Commentaries | A portfolio of written commentaries applying economic theory to real-world news articles. Each commentary analyses a current economic event using relevant theory. |
Group 3 — Individuals & Societies: Business Mgmt | Business Management (HL/SL) | Business IA (Research Project) | HL: a 1,800-word research project investigating a real business issue. SL: a 1,500-word commentary. Requires primary research methods and structured analysis. |
Group 3 — Individuals & Societies: Psychology | Psychology (HL/SL) | Experimental Report | A written report of an experimental study using a student-designed simple experimental method. Structured as a formal scientific report. |
Group 4 — Sciences | Biology, Chemistry, Physics, ESS (all HL/SL) | Scientific Investigation | A written report of a student-designed scientific investigation. Includes research question, methodology, data collection, analysis, and evaluation. Includes a Group 4 collaborative project component. |
Group 5 — Mathematics | Math Analysis & Approaches (HL/SL); Math Applications & Interpretation (HL/SL) | Mathematical Exploration | A written exploration of a mathematical topic of personal interest, typically 6–12 pages. Internally marked by teacher; externally moderated by IB examiner. |
Group 6 — The Arts | Visual Arts (example) | Comparative Study + Portfolio | Includes a comparative study of 10–15 artworks, a process portfolio, and an exhibition. In some Arts subjects the IA can account for up to 100% of the final grade. |
Group 1 — Studies in Language and Literature
In Group 1 subjects (English Language and Literature, and Language A literature courses), the IA takes the form of the Individual Oral (IO). This is a 15-minute oral examination in which you analyse and discuss extracts from one literary text and one body of work (a non-literary text or a set of texts), exploring a global issue of your choice that connects them. Your teacher assesses your oral performance and submits the recording for external moderation. Preparation and practice are essential: the IO rewards students who can sustain a structured analytical argument under examination conditions, not those who have simply memorised a script.
Group 2 — Language Acquisition
Group 2 subjects (Language B at HL and SL, and ab initio) also use an Individual Oral (IO) format, though the structure differs from the Group 1 IO. The Language B oral assesses communicative competence: your ability to understand, engage with, and discuss content in the target language. You examine a visual stimulus and discuss a related global issue, demonstrating range of vocabulary, grammatical accuracy, and communicative fluency. Teacher-assessed and externally moderated.
Group 3 — Individuals and Societies
Group 3 covers History, Economics, Business Management, Psychology, and related social science subjects. Each has a distinct IA format reflecting its disciplinary methods:
- History: History IA guide — The Historical Investigation is a 2,200-word written investigation into a historical question of your choosing. It includes evaluation of sources, a structured argument, and a reflection on the historian’s methods. Source selection and critical analysis are the primary skills assessed.
- Economics: Economics IA guide — A Portfolio of Commentaries — a set of written responses in which you apply economic theory to real-world articles from news sources. Each commentary demonstrates your ability to connect theoretical models to current economic events.
- Business Management: The Business IA (Research Project) involves primary research into a real business issue. HL students write a 1,800-word project; SL students write a 1,500-word commentary. Research design and business analysis tools are central to this IA.
- Psychology: An Experimental Report based on a simple experimental study of your own design. Written up in a formal scientific report format, it assesses your ability to apply experimental methodology and interpret results.
Group 4 — Sciences
For Biology, Chemistry, Physics, and Environmental Systems and Societies (ESS) at both HL and SL, the IA is a Scientific Investigation — a written report of an inquiry you have designed and conducted yourself. It includes a clear research question, a justified methodology, raw data collection, quantitative analysis, and a critical evaluation of your process and findings. Examiners assess the quality of your scientific thinking, not just the accuracy of your results.
Group 4 students also complete a Group 4 Project — a collaborative, interdisciplinary activity undertaken with students from other science subjects. This project contributes to the Engagement component of the science IA assessment. It is not a separate IA submission; its purpose is to develop collaborative and cross-disciplinary scientific skills.
Group 5 — Mathematics
Both Mathematics Analysis and Approaches (Math AA) and Mathematics Applications and Interpretation (Math AI) at HL and SL use the Mathematical Exploration as their IA format. This is a written exploration, typically 6–12 pages, in which you investigate a mathematical topic of personal interest. You are assessed on your ability to identify a clear mathematical focus, apply relevant mathematical content, reason critically, and reflect on the significance of your findings. Choosing a topic with genuine personal relevance significantly strengthens the Personal Engagement criterion, which is one of the assessment dimensions. Explore Math IA topics and ideas to find an exploration direction that connects to your interests.
Group 6 — The Arts
Arts subjects — such as Visual Arts, Music, Theatre, and Dance — have highly varied IA formats that reflect the creative and evaluative nature of the discipline. In Visual Arts, for example, the IA includes a comparative study (analysing 10–15 artworks), a process portfolio documenting creative development, and an exhibition. The IA weighting in some Arts subjects can account for a significantly larger proportion of the final grade than in other subject groups — in some cases representing the entirety of the assessment for a component. If you are studying an Arts subject, verify the exact IA structure with your teacher or IB school coordinator.
How Much Is the IB Internal Assessment Worth?
The IA’s contribution to your final subject grade is not uniform across the Diploma Programme — it varies by subject group and, in some cases, by level (HL vs SL). Understanding this variation helps you prioritise your effort appropriately across your six subjects.
For most IBDP subjects, the IA accounts for approximately 20–30% of the final subject grade, with the remaining percentage determined by written examinations.
Within the sciences (Group 4), the IA typically contributes around 20% for both HL and SL. Within mathematics (Group 5), the Mathematical Exploration contributes 20%.
In the Individuals and Societies group (Group 3), the weighting varies by subject: Economics and Business Management IAs typically contribute 20%, while the Psychology Experimental Report and History Historical Investigation contribute higher proportions.
Arts subjects (Group 6) represent the most significant exception. In Visual Arts, for instance, the combined IA components can account for the majority of the final grade. It is essential to verify the exact weighting for your specific subject with your school’s IB coordinator or subject teacher, as these details are subject to IB curriculum updates.
What the weighting means in practice: a student who achieves a strong examination score but submits a weak IA will find their subject grade pulled down by that IA component.
Equally, a student who struggles in examinations has a genuine opportunity to secure marks through a well-executed IA. Neither component can be treated as secondary — both matter, and both respond to preparation and expert guidance.
IA vs. Extended Essay: What’s the Difference?
The IA and the Extended Essay (EE) are both assessed written components of the IBDP, but they serve different purposes and operate under very different structures.
The IA is a subject-specific coursework component — every student completes one IA for each of their six subjects, in a format defined by that subject’s curriculum.
The EE is a standalone 4,000-word independent research essay on a topic of the student’s choosing, completed once across the two years of the Diploma.
The IA is an integral part of each subject’s assessment; the EE is a separate core requirement of the Diploma as a whole. For a complete step-by-step breakdown of the EE process, read our complete IB Extended Essay guide.
Tips for a Strong IB Internal Assessment
The following tips are drawn from what our certified IB examiners observe during the May and November moderation process. These are not generic study strategies — they reflect the patterns that consistently separate well-scoring IAs from those that leave marks on the table.
- Choose a topic with genuine personal relevance. Our examiners can identify authentic intellectual curiosity in the way a student frames their investigation and evaluates their results. An IA on a topic the student genuinely cares about demonstrates more natural engagement with the subject matter — and engagement is assessed directly under many IA criteria. Choose something that connects to your own experiences, interests, or questions, then build the academic rigour around that starting point.
- Formulate a precise, answerable research question before you begin. The research question anchors your entire IA. A vague or overly broad question produces a vague or overly broad investigation, which loses marks under multiple criteria simultaneously. Your question should be specific enough that you can genuinely answer it within your subject’s word or page limit, and arguable enough that your analysis can go beyond simple description. Every section of your IA should contribute to answering it.
- Follow the mark scheme from the first draft, not the last. Every IBDP subject publishes its IA assessment criteria as part of the subject guide. Students who write their IA without consulting these criteria regularly miss scoring opportunities that were entirely available to them. Before you write a single paragraph, read the criteria for your subject. Structure your investigation around what is explicitly rewarded, not around what feels intuitive. Our certified examiners consistently observe this as one of the highest-impact habit changes for IA students. For subject-specific guidance on applying these criteria, explore IA and EE guidance from £55 per hour.
- Plan your word count before you write. Every IA has strict length requirements — 2,200 words for the History Historical Investigation, 6–12 pages for the Mathematical Exploration, and so on. Going significantly over these limits is not an indication of thoroughness; it signals poor scope management to the examiner. A focused IA that answers a well-chosen question within its word limit demonstrates far stronger investigative design than an overlong exploration that meanders across multiple questions.
- Build a genuine feedback and revision cycle with your teacher. Your first draft is a working document, not a submission. Students who treat the first draft as final almost always score below their genuine potential, because teacher feedback exists specifically to identify where the IA’s argument, methodology, or presentation can be strengthened. Give yourself enough time to receive substantive feedback, act on it thoughtfully, and submit a revised version — not a first draft under time pressure.
Common Mistakes in the IB Internal Assessment
The following mistakes appear consistently in Internal Assessments assessed during IB moderation. Our certified examiners observe these patterns across subjects and examination sessions. Each one is avoidable at the planning stage — which is why understanding them before you begin is more valuable than trying to correct them after a first draft is written.
Mistake 1: Descriptive writing where analysis is required One of the most consistent patterns our certified examiners observe in moderation is an IA that narrates what happened or what the data shows, rather than evaluating what it means. In a Biology Scientific Investigation, describing that a variable changed is not analysis — explaining why it changed, whether the change was statistically meaningful, and what limitations might affect that interpretation is analysis. In a History Historical Investigation, describing an event is not argument — evaluating the significance of conflicting sources and drawing a supported conclusion is argument. If your IA reads like a summary, it is not yet an IA. |
Mistake 2: A research question that is too broad for the format Our examiners consistently find IAs where the student has selected a research question that cannot be adequately investigated within the available word count or timeframe. An Economics commentary on ‘the effects of inflation’ is not a commentary — it is a macroeconomics textbook chapter. A History investigation into ‘the causes of World War Two’ cannot be answered in 2,200 words with any analytical depth. A well-scoped research question is narrow enough to investigate thoroughly and broad enough to generate genuine analysis. If your question could be the title of a textbook chapter, narrow it. |
Mistake 3: Inconsistent or absent citation and referencing Our certified examiners regularly identify IAs in which the bibliography does not match the sources cited in the body text, or in which sources are used but not cited at all. This is not a minor formatting oversight — it directly affects marks across multiple assessment criteria, including the evaluation of sources and the integrity of the academic presentation. Before submission, conduct a citation audit: verify that every source cited in the body appears in the bibliography, that every source in the bibliography was actually used, and that your citation style is consistent throughout. |
Mistake 4: Writing the IA first, then checking the criteria last Students who approach the IA as a writing task — rather than as an assessed task with published criteria — consistently leave marks available on the table. The IB’s assessment criteria for each subject are not a secret; they are published in the subject guide and available to every student. Our examiners observe IAs that demonstrate genuine intellectual effort but miss specific criterion requirements entirely, simply because the student did not reference the criteria during writing. Read the criteria before you begin. Refer to them while you write. Use them as a checklist before you submit. |
Get Expert IA Guidance from IB Innovators
The Internal Assessment represents a meaningful portion of your final IB subject grade — and scoring well on it requires more than effort alone.
It requires knowing what examiners look for when they moderate: how the assessment criteria are applied, what separates an analytical argument from a descriptive one, and where the most common scoring gaps appear. That knowledge comes from experience inside the moderation process, not from studying student guides.
At IB Innovators, our IA guidance is delivered by Senior IB Examiners with 7+ years of subject mastery who participate actively in May and November moderation sessions.
They know what the IB’s standards look like because they apply them. Students supported through IB Innovators IA guidance have improved their subject grades by multiple grade boundaries across Chemistry, Mathematics, and the Individuals and Societies group.
Our IA guidance sessions are conducted on our our online learning platform online platform, with digital whiteboard tools and recorded sessions you can revisit between meetings.
Our tutors provide structured feedback, direction, and quality improvement strategies at every stage of the IA — from topic selection and research question formulation through to final submission review. Our tutors do not write the Internal Assessment for students — they guide the process so that the IA you submit is genuinely and verifiably yours.
Every enquiry begins with a complimentary 30-minute consultation — free, no payment required, no obligation. We assess your subject, your current IA stage, and your timeline, then match you with an examiner who has specific moderation experience in your subject group.
Book Your Free 30-Minutes Consultation Work with a certified IB examiner on your Internal Assessment — from topic selection to final submission. |
Frequently Asked Questions
The IB Internal Assessment (IA) is an assessed coursework component that forms part of every subject in the IB Diploma Programme (IBDP).
It is marked by your subject teacher using the IB’s published assessment criteria and then externally moderated by an IB examiner. Every IBDP subject includes an IA, though the format — whether a written investigation, an oral examination, a scientific report, or a mathematical exploration — varies by subject group.
The IA’s contribution to your final subject grade varies by subject. For most IBDP subjects, the IA accounts for approximately 20–30% of the final grade, with written examinations making up the remainder.
The exact percentage differs by subject: sciences typically 20%, mathematics typically 20%, with variation across the Individuals and Societies group.
Some Arts subjects assign a significantly higher proportion — in some cases the majority of the grade — to IA components. Confirm the precise weighting for your subject with your school’s IB coordinator.
Every subject in the IB Diploma Programme (IBDP) includes an Internal Assessment component. The IA is not optional or limited to certain subject groups — it is a standard part of all six Group subjects: Group 1 (Language and Literature), Group 2 (Language Acquisition), Group 3 (Individuals and Societies), Group 4 (Sciences), Group 5 (Mathematics), and Group 6 (The Arts). The format varies significantly across groups, from oral examinations to written investigations to mathematical explorations.
The IA is assessed through a two-stage process.
First, your subject teacher marks your completed IA using the IB’s published subject-specific assessment criteria — this is the internal assessment stage.
Second, the IB selects a sample of marked IAs from your school and sends them to a certified IB examiner for external moderation. The examiner checks that your teacher’s marking aligns with the IB’s expected standards. If the examiner identifies a systematic difference, all students’ marks from the school are adjusted proportionally.
The Internal Assessment (IA) is a subject-specific coursework component: every student completes one IA for each of their six IBDP subjects.
The Extended Essay (EE) is a separate core requirement: a single 4,000-word independent research essay completed once across the two years of the Diploma, in a subject of the student’s choosing.
The IA is integral to each subject’s grade; the EE is assessed separately and contributes to the diploma alongside Theory of Knowledge (TOK).
Yes — and targeted expert support at the right stage of the IA process can make a meaningful difference to the quality of your final submission. IB Innovators IA guidance (from £55 per hour) is delivered by Senior IB Examiners with 7+ years of subject mastery who moderate Internal Assessments in the May and November IB examination sessions. Our tutors support research question formulation, methodology design, argument development, and final revision — but do not write the IA for students. Every enquiry begins with a free 30-minute consultation.
