Internal Assessment Meaning: What Is an IB IA?
Jamal Lewis
If you are new to the IB Diploma Programme, you have probably heard teachers mention the IA and wondered what it actually is. Internal assessment is one of the most important parts of your IB experience, yet the name alone does not tell you much. This guide explains the internal assessment meaning in plain language, how IAs fit into IB grading, and what you should expect as a student or parent.
What Does Internal Assessment Mean?
In the IB Diploma Programme, internal assessment (IA) refers to coursework completed during the two-year programme that is first assessed by your classroom teacher. The IB then reviews a sample of student work through a process called moderation to ensure marking is fair and consistent worldwide.
The word internal does not mean the work stays hidden or informal. It means the initial grading happens inside your school, by someone who teaches the subject and knows the IB criteria. External assessment, by contrast, is work marked directly by IB examiners, such as your final written exams in May or November.
Internal vs External Assessment in IB
Most IB subjects use a mix of both assessment types. External exams test what you know under timed conditions at the end of the programme. Internal assessments test what you can produce over weeks or months: a lab report, a mathematical exploration, a historical investigation, a commentary, or a performance, depending on the subject.
The IB uses internal assessment because many skills cannot be measured in a single exam. Research, data collection, extended writing, and practical work all need time and feedback. Your IA is where you show those skills in a subject-specific project.
What Does an IA Look Like in Practice?
There is no single IA format across all subjects. In Group 4 sciences, you typically design and carry out an experiment. In Mathematics, you write an exploration on a topic you choose. In History, you complete a historical investigation. In Economics, you write commentaries on real news articles. Languages may include oral assessments or written tasks recorded and submitted for moderation.
What these tasks share is that you work on them during the course, follow IB criteria, and receive a grade that counts toward your final subject result. An IA is not regular homework. It is a formal piece of assessed work with clear requirements, deadlines, and mark schemes.
How Are IAs Graded?
Your teacher marks your IA using IB assessment criteria published for each subject. They assign marks for specific strands, such as research design, analysis, or communication, rather than giving a vague overall impression.
After internal marking, the IB moderates a sample of work from your school. If marking across the cohort is too generous or too harsh compared with global standards, the IB may adjust marks for the whole group. That is why the grade on your draft is not always your final moderated result. Your teacher's feedback still matters enormously, because strong drafts usually become strong final submissions.
How Much Do IAs Count Toward Your Final Grade?
The weighting varies by subject, but internal assessment usually makes up a meaningful share of your final mark. In many sciences and Mathematics, the IA is often around 20% of the subject grade. In some humanities and language courses, coursework components can weigh more. Your subject guide or teacher will confirm the exact percentage for your course and level (SL or HL).
Because IAs count toward your diploma results, treating them as optional side projects is a common mistake. A weak IA can pull down an otherwise strong exam performance. A well-planned IA can protect your grade when exam day does not go as planned.
Which IB Subjects Have Internal Assessments?
Most DP subjects include some form of internal assessment, though the name and format differ:
- Sciences (Biology, Chemistry, Physics): individual scientific investigation
- Mathematics: internal exploration
- Individuals and societies (History, Economics, Business, Psychology, and others): investigations, commentaries, or research projects
- Language and literature: oral and written coursework components
- The arts: performances, portfolios, or process portfolios
If you are still choosing a topic, subject-specific idea lists can help. Browse guides like our Biology IA topic ideas, Chemistry IA topics, or Economics IA ideas once you understand the basics.
IA vs EE, TOK, and CAS
Students often confuse the IA with other IB requirements. They are related, but not the same thing.
- Internal Assessment (IA): subject coursework that counts toward each individual subject grade
- Extended Essay (EE): a separate 4,000-word research essay that earns its own grade and contributes up to 3 bonus points with TOK
- Theory of Knowledge (TOK): assessed through an exhibition and essay, not a subject IA
- CAS (Creativity, Activity, Service): a pass/fail requirement based on experiences and reflections, not a graded coursework mark
You will juggle all of these at once, which is why planning matters. Our guide on balancing IA, EE, CAS, and exams is a useful next read once you know what each component involves.
When Should You Start Your IA?
Most students begin IA planning in the first year of the DP and complete the bulk of the work across Year 1 and early Year 2. Exact deadlines are set by your school, not the IB globally, so two students at different schools may have very different timelines.
The practical advice is simple: choose a focused topic early, check it with your teacher, and leave time for revisions after feedback. Last-minute IAs rarely score well because moderation rewards work that meets criteria clearly, not work that was rushed to meet a deadline.
What Makes a Strong IA?
High-scoring IAs tend to share a few traits: a clear and manageable research question, methodical work, honest analysis, and writing that follows the IB criteria line by line. Originality matters, but so does feasibility. The best topic is one you can actually investigate well with the time, equipment, and data available to you.
Read the mark scheme before you start, not after your first draft. If you want a full walkthrough of the process, see our step-by-step IA writing guide. For examiner-focused advice, tips to impress your examiners is another strong resource.
On Baccalytics, students and teachers use subject practice and performance analytics to spot weak areas before exams. The same mindset helps with IAs: know the criteria, practise the skills the task demands, and track where you are losing marks.
Common Misconceptions About Internal Assessment
- "IA" is not one universal assignment. Each subject has its own task, criteria, and word limits.
- Your teacher's mark is not always the final result until IB moderation is complete.
- An IA is not the same as a final exam. Both count, but they measure different things.
- The MYP also uses internal assessment, but DP IAs are separate, more demanding, and tied to your diploma subject grades.
Key Takeaways
Internal assessment means coursework assessed first by your teacher and then moderated by the IB. It counts toward your subject grade, takes a different form in each subject, and rewards careful planning as much as raw talent. Understand the criteria, start early, and use feedback before your final submission.
Now that you know what an IA is, pick your subject, explore topic ideas, and build a timeline that leaves room for real revision. That is how you turn the internal assessment from a source of stress into one of the most controllable parts of your IB results.