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How to write MYP Maths Criterion C Assessments - Tips and Examples

Updated: Jul 31, 2022

Communication is a common feature in the IB; it appears as an ATL skill, a learner profile trait and again as an assessment objective. Let’s break down how we assess communication in MYP Mathematics.

The criterion strands

i. use appropriate mathematical language (notation, symbols and terminology) in both oral and written explanations

- Give an opportunity for students to use the keywords introduced in the unit.

- It should be clear that students should always use, and recognise, the mathematical notation given in the maths guide (pages 47 - 50)

- Opportunities to present, teach or create a video will allow oral explanations

ii. use appropriate forms of mathematical representation to present information

iii. move between different forms of mathematical representation (not in year 1)

-Forms of mathematical representation include: written explanations, calculations, diagrams, tables, graphs, lists, formula/ratio triangle, conversion loops, flowcharts, number lines, formulae, proof and essentially anything that SHOWS their thinking.

-The most “appropriate forms” of representation should have been modelled throughout the unit - if they would be expected to draw a graph in the assessment, time should be spent on how to scale axes. With trigonometry they should have seen how to label the sides of a triangle. If looking at algorithms they should know they correct symbols for a flowchart and have had practice drawing them. For proof, they should understand how to lay that out.

- "Moving between" appropriate forms could involve creating them, or interpreting them. So make sure pupils have experience with both.

- Interpretation of simulations, images, videos, animations, data tables and graphs will be required for the e-assessment.

iv. communicate coherent (year 1+), complete (year 2+) and concise (year 4+) mathematical lines of reasoning

-Coherent - does it flow? Is it clear to the audience where answers came from or how a diagram links to a conclusion?

- Complete - share all thinking, calculations and steps. Sometimes it helps to give the project a mock audience of someone a few years younger than the class, so they remember to explain what they are doing.

- Concise - refine and share what is necessary. Particularly in reports, it is important points aren’t repeated while still ensuring communication is complete and flows.

v. organize information using a logical structure.

-Beginning, middle, end - title, introduction to explain the investigation or problem, main body showing the processes they took, conclusion with final rule (criterion B), answer or reflection (criterion D).

- In a report, subheadings can help to guide the reader

- In a presentation, each slide should have its own purpose

- In a poster, it should be clear what direction to read the information

- A video should still have a beginning, middle, end

What it says in the guide

“Criterion C is often used to assess constructed responses and reports in combination with criterion B or D.” (page 31)

“Investigations and real-life problems

Reports that:

• require logical structure

• allow multiple forms of representation to present information.

Criterion C is often used when students present a report, for example, that requires a logical structure in order to be followed and that would allow for several forms of representation to be used to present information.” (page 31)

In reference to the e-assessment: “For example, a question assessing knowledge and understanding may also require students to move between different

forms of mathematical representation.” (page 47)

Some examples

  • A poster to show the impact of vaccinations on measles outbreaks around the world. Include data tables from different countries, algebraic and graphical communication of exponential functions. (criteria C, D)

  • An investigation on how to set the rules to make certain dice games “fair” may involve sample space diagrams showing how different rules result in different outcomes. A slideshow presentation would clearly distinguish between the different investigations on each slide. (criteria B, C)

  • An instructional video about writing numbers as composition of prime factors would assess the use of mathematical language verbally. (criteria A, C)

  • Through a video, animation or set of images, students can see an investigation or mathemagic trick being completed step by step. Their task is to create a flow chart which outlines the steps that have been taken. Nrich has some great ones!

Good practice and tips

-Not every strand has to be assessed - either structure the assessment to ensure students can meet every strand or critique your assessment and remove the ones that do not seem applicable.

-In the younger years, give students a checklist of what to include to aid reflection before submitting. This can be in addition to the task-specific clarification. It can include “my introduction mentions which sport I am investigating” or “my work falls under the subheadings: patterns, rule, verification, justification” or “my conclusion talks about how accurate my answer is”.

-Criterion C is assessed alongside A, B and D in the e-assessment so it is beneficial for students to see it in different contexts beforehand. Criteria A can easily be as a response to a visual aid or require mathematical language/notation and involve showing working. It will be harder to assess some of the strands in a test format so save strand v), for example, for another assessment.

-If criterion C is assessed with another criterion, make sure it is clear to the students (and you) how each question will be graded. Give students an opportunity to be successful on C even if they can not find a rule or solve the real-life problem.

- Prior to the summative, encourage peer assessment (in a safe and positive environment). If a student is struggling to follow what another student created, give them a constructive outlet to give feedback.

Here are two examples of criterion C being assessed within an investigation and real-life problem. They include the task, assessment rubric, task-specific clarifications, sample student answer and marking guidelines.



Jo Fong Ching Min
Jo Fong Ching Min
Apr 30, 2023

I find it quite hard to separate coherence into 4 levels for MYP1. Any tips?

Teaching MYP Maths
Teaching MYP Maths
May 18, 2023
Replying to

It depends on the task but it can help to view it as rarely (1-2), often (3-4), mostly (5-6) always (7-8) clear in terms of calculations shown and sentences written (or spoken).


This is so insightful. Thanks a lot for sharing


Sayem Ahmed kosru
Sayem Ahmed kosru
Jul 31, 2022

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