Your IB Maths IA — done properly.

The complete guide to planning, writing, and submitting a top-scoring Mathematical Exploration. Free tools for every stage — for AA & AI, SL & HL.

💡
Topic Ideas
📅
IA Planner
📊
Criteria Guide
Checklist
⚠️
Pitfalls

What is the Maths IA?

The Internal Assessment — officially called the Mathematical Exploration — is a piece of independent written work worth 20% of your final IB Maths grade. It is marked by your teacher and then moderated externally by the IB, so the same mark scheme applies to every student in the world.

Unlike your exams, the IA is completed during the course with no time pressure. You choose your own topic, investigate it at your own pace, and submit a polished written exploration. That makes it one of the most controllable parts of the IB — and with the right approach, one of the easiest places to score well.

The exploration is not a history-of-maths essay, a biography of a mathematician, or a summary of a textbook chapter. It is an active mathematical investigation: you do calculations, build models, test hypotheses, and reflect on what you find. The IB wants to see you doing mathematics, not describing it.

20%
of your final IB Maths grade
12–20
pages recommended
20
marks available
5
marking criteria
Good news: Unlike exams, the IA is entirely in your control. A student who plans carefully, picks the right topic, and understands what examiners want can score close to full marks regardless of how they perform under timed conditions.

How should it be structured?

There is no single compulsory format, but examiners consistently reward explorations that follow a clear, logical structure. A strong IA typically has these seven components:

1

Title

A precise, specific title that tells the reader exactly what you investigated — not just "The Mathematics of Music" but "Modelling the Relationship Between Tempo and Emotional Response Using Regression Analysis."

2

Introduction & Rationale

Explain the context of your topic and — crucially — your personal reason for choosing it. State your aim clearly: what question are you trying to answer? This is where personal engagement marks are earned or lost. Keep this section to 1–2 pages; don't pad it with general background.

3

Mathematical Background

Briefly introduce any theory the reader needs to follow your work. Define all variables and notation here. Don't overdo this — examiners don't need you to re-derive the quadratic formula. Include only what is genuinely necessary to understand your exploration.

4

Exploration (main body)

The largest section — where you actually do the mathematics. Present your calculations, models, graphs, and tables clearly. Show all working. Connect each result back to your aim: don't just calculate — interpret. Weave in reflection as you go rather than saving it all for the end. This section earns most of your marks on Criteria B, D, and E.

5

Conclusion

Answer your original question directly. Summarise the key findings without simply restating everything you've already written. Discuss whether the results matched your expectations and what they mean in the real-world context of your topic.

6

Reflection

Acknowledge the limitations of your approach — the assumptions you made, the data you couldn't obtain, the models that oversimplify. Suggest meaningful extensions: what would you do differently? What could be explored further? This earns Criterion D marks and is often where students leave marks on the table.

7

Bibliography

List every source you used. Use a consistent format (MLA or APA) and cite within the text wherever you quote or use an idea from elsewhere. Academic honesty is taken seriously — a missing bibliography can trigger a formal review.

Formatting tip: The IB recommends using a standard word processor with size-12 font and double spacing. Aim for 12–20 pages of content (not counting the bibliography and appendices). Graphs and tables must appear in the body of the text — not as appendices — and must be clearly labelled.

The five marking criteria

Every IB Maths IA is marked against the same five criteria, totalling 20 marks. Understanding exactly what each criterion rewards — and what it penalises — is the single most valuable thing you can do before you start writing.

A Presentation
4 marks

Is the exploration well-organised, coherent, and easy to follow? Every graph labelled, every table titled, logical flow from start to finish.

B Mathematical Communication
4 marks

Is notation used correctly and consistently? Are variables defined? Do you use multiple forms of representation (equations, graphs, tables)?

C Personal Engagement
3 marks

Does the exploration feel genuinely yours? Is there evidence of independent thinking, creativity, or a personal connection to the topic?

D Reflection
3 marks

Do you critically evaluate your results, acknowledge limitations, and suggest meaningful extensions — throughout the exploration, not just at the end?

E Use of Mathematics
6 marks — the most important criterion

Is the mathematics relevant, accurate, and sufficiently sophisticated? SL: go beyond routine procedures. HL: demonstrate genuine HL-level content. Examiners penalise maths that is too simple for the level.

Criterion E is worth 6 of the 20 marks. A beautifully written IA with weak mathematics will not score well. Make sure the mathematical content is at — or preferably beyond — the level of your course before you worry about presentation.

What does a top-scoring IA look like?

Students who score 18–20 out of 20 consistently share the same qualities. Here's what distinguishes a Grade 7 IA from an average one:

🎯 A specific, personal topic

The best IAs come from genuine curiosity. "I fractured my wrist and wanted to understand the biomechanics of bone stress" will always outscore "I chose statistics because I like sport." The more specific the question, the deeper the mathematics.

🧮 Sophisticated mathematics

Top explorations use mathematics at or above the course level — differential equations, regression modelling, hypothesis testing, calculus optimisation — applied correctly and interpreted meaningfully. Simple arithmetic or basic averages will not score above 4/6 on Criterion E.

💭 Reflection woven throughout

Don't save all your reflection for the conclusion. After each result, ask: What does this mean? Does it make sense? What assumptions did I make? What would change if I modified the model? Examiners reward reflection that is embedded in the work.

📐 Impeccable communication

Every variable defined. Every graph labelled. Notation consistent from page 1 to page 18. Examiners should never have to guess what a symbol means. Use an equation editor for all mathematical expressions — never write equations by hand or paste them as images.

📊 Real or self-collected data

If your exploration uses data, collecting it yourself — measuring, surveying, recording — scores far better on personal engagement than downloading a generic dataset. If you must use secondary data, justify your specific choice and show what you added to the analysis.

🔄 Honest limitations

No model is perfect, and examiners know that. Identifying your own limitations shows mathematical maturity. "My model assumes a constant carrying capacity, which may not hold seasonally — a worthwhile extension would be to model K as a periodic function" is exactly the kind of reflection that earns full marks on Criterion D.

The examiner reads hundreds of IAs. A memorable, genuinely curious exploration stands out immediately. Don't copy a topic from a list — find something you actually want to investigate, then build the mathematics around it.

SL vs HL — what's the difference?

The IA counts for 20% of your final grade regardless of whether you are SL or HL, and the same five criteria apply. The key difference is the expected level of mathematical sophistication in Criterion E.

SL students are expected to go beyond routine procedures — simple statistics or basic algebra will not score highly. Regression analysis, modelling with functions, or inferential statistics (hypothesis testing, chi-squared) are appropriate SL-level mathematics.

HL students must demonstrate genuine HL content. Differential equations, complex numbers, advanced calculus, eigenvalues, or the HL statistics topics are expected. An HL student who writes an SL-level exploration will be marked down on Criterion E regardless of how well they perform on the other four criteria.

AA vs AI: The choice of analysis or applications course should influence your topic. AA students suit pure exploration of mathematical structure (proof, sequences, complex analysis). AI students suit data-driven, modelling, and statistics-heavy topics. Both are equally valid — what matters is that the maths is relevant and sophisticated.

Ready to get started?

Use the free tools in this guide to plan, write, and polish your IA — step by step.

💡 Topic Idea Bank

Browse 35+ topic ideas. Filter by theme, level, or course — or search by keyword.

📅 IA Planner & Timeline

Follow the 7 stages of a strong IA, and generate a personal timeline from your submission date.

Generate your timeline

The 7 stages of a strong IA

📊 Criteria Guide

The IB Maths IA is marked out of 20 across 5 criteria. Learn exactly what examiners look for.

✅ Pre-Submission Checklist

Work through every item before handing in your IA. Aim for 100%.

⚠️ Common Pitfalls

The most frequent mistakes IB examiners see — and exactly how to avoid them.