---
title: "A Guide to IB Internal Assessments Across Every Subject"
description: "How IB Internal Assessments work, when to start, how to pick a topic, and what top-scoring IAs share, with answers to common parent and student questions."
url: https://bosenacademics.com/blog/ib-internal-assessment-guide/
published: 2018-09-04T08:00:00Z
updated: 2026-11-12T17:05:00Z
section: "IB Diploma"
publisher: Bosen Academics (https://bosenacademics.com)
---

# A Guide to IB Internal Assessments Across Every Subject

**The short answer:** IB Internal Assessments are teacher-marked coursework pieces, moderated by the IB, that make up 20 to 30 percent of the grade in most subjects. Start choosing a topic early in Year 1, keep it narrow and personally interesting, and write against the published criteria. Strong planning is the main difference between a high and a low IA mark.

Internal Assessments (IAs) are among the most misread parts of the IB Diploma. In most subjects they carry 20 to 30 percent of the final grade, which makes them a big scoring opportunity, and many students only realize this when it is nearly too late. Exams give you one sitting. An IA gives you time to research, draft and revise, so with sound planning a low mark is rarely necessary.

## What Are IB Internal Assessments, Exactly?

An IA is a piece of coursework that your teacher marks and the IB then moderates. Its form depends on the subject. Sciences ask for a written report on an investigation you design yourself, math asks for a mathematical exploration, and English asks for an individual oral commentary. Each subject guide publishes its own criteria, and meeting every one of them is how strong scores are earned.

Do not let the word “internal” mislead you. Your teacher gives the first grade, but the IB samples IAs from every school and checks them for consistency. In other words, your teacher’s marking is measured against international standards, and the scores can move up or down.

## When Is the Right Time to Begin Your IA?

Begin thinking about a topic as early as you can in Year 1. Plenty of students wait until Year 2 for serious work, and that adds pressure on top of exam preparation. A good schedule has the topic chosen and approved by the end of Year 1, and data collection or primary research finished over the summer. Year 2 is then free for writing, refining and polishing.

## How Do You Pick a Good IA Topic?

Strong topics have three things in common. The student finds them interesting, they are narrow enough to cover properly within the word limit, and they allow real analysis instead of plain description.

Typical errors are topics that are too broad (a whole country’s economy), too simple (a basic titration whose result is obvious) or too ambitious (needing equipment or data the student cannot get). A good Math IA might look at the mathematics behind a real-world pattern the student has noticed, instead of trying to prove a theorem that already exists.

## What Do the Best IAs Have in Common?

Across subjects, top-scoring IAs tend to show the same traits:

- **A clear structure** that follows the assessment criteria directly
- **Personal engagement** that is visible without feeling forced
- **Critical analysis** that is honest about limitations
- **Precise academic language** that suits the subject
- **Careful citation** all the way through, not only in the bibliography

### Related Reading

- [IB Math AA HL exam preparation](https://bosenacademics.com/blog/ib-math-aa-hl-exam-prep/)
- [A parent’s guide to IB Diploma success](https://bosenacademics.com/blog/parent-guide-ib-diploma/)
- [How AA and AI differ in IB Math](https://bosenacademics.com/blog/ib-math-aa-vs-ai/)

IB Internal Assessments reward careful planning, real engagement and close attention to the criteria. If your child wants help at any stage, from choosing a topic to the final read-through, [book a free consultation with Bosen Academics](https://bosenacademics.com/consultation/). Our IB-certified educators have supported students through IAs in every subject and know what moderators look for.

## Frequently asked questions

### How long should an IB Internal Assessment be?

It depends on the subject. The Math exploration is typically around 12 to 20 pages, the science investigation report has a maximum of 3,000 words, and the Economics IA is a portfolio of three commentaries of 800 words each. Check the current subject guide, because limits are strictly enforced.

### Can a tutor help with my IA?

Yes, within limits. A tutor can help you brainstorm topics, understand the criteria, review drafts and suggest improvements. A tutor cannot write any part of the IA or supply content you present as your own, and violations can cost you the diploma.

### What happens if I score poorly on my IA?

Strong exam results can partly make up for a weak IA, but it is an uphill climb. If the IA is worth 25% of a subject grade, lost IA marks mean you must do even better on the exam to reach your target, so prevention is easier than recovery.

### Does the IB check my teacher's marks?

Yes. The IB moderates a sample of IAs from every school, so a teacher's marks are compared with international standards and can be adjusted up or down.

## Tutoring from Bosen Academics

One-on-one tutoring from certified teachers and subject experts with master's and PhD degrees, in person in North York, Toronto, or online. Book a free consultation: https://bosenacademics.com/consultation/