On a Sunday evening, a Grade 9 student we will call Meera sits at the kitchen table with her maths unit test. Most of her answers are right, and she knows the content well. Yet the paper comes back with a red comment asking her to show how she reached her answers. Her parents are puzzled, because the maths is not the problem. The gap is in how that maths is presented, and in the MYP that presentation is assessed separately.
Criterion C rewards clear, correct and complete communication of mathematical thinking. Most of the marks students lose here come from missing reasons, unlabelled work and loose notation, and all of these can be fixed with deliberate practice rather than a full relearning of the topic.
What Criterion C actually asks for
Criterion C sits alongside Knowing and Understanding, Investigating Patterns and Applying Mathematics in Real-Life Contexts. It is about communication: using mathematical language and notation correctly, setting out solutions in a logical order, and showing enough reasoning that a reader can check every step. The command terms in an assignment are a good guide. When a question says justify, explain or show that, a bare answer will not earn full credit.
The four habits that quietly cost marks
- Answers without working. A final value with no visible method forces the marker to guess what was done.
- Missing justification sentences. A line such as the gradient is negative, so the function is decreasing earns credit; the calculation alone does not.
- Unlabelled graphs and diagrams. Axes need names and units, lines need labels, and a sketch should show the features the question asks about.
- Loose notation. Using an equals sign to join expressions that are not equal, dropping units, or leaving brackets out makes an argument hard to follow, even when the answer is correct.
Turning good reasoning into a home habit
Talking through a worked example aloud is one of the quickest ways to build the habit. Ask your child to explain each step as they go, then write down only what they said. After each question, a useful check is to reread the command term and confirm it has been answered in a full sentence. If a question asks for rounding, the degree of accuracy should be stated, and in a real-life problem the final answer should be linked back to the context in one sentence.
A quick self-check before handing in
- Does each line follow logically from the one above it?
- Is every graph, table and diagram labelled, with units where they apply?
- Has each command term been answered in a complete sentence?
- Does the final answer match the context and the required degree of accuracy?
How small batches make Criterion C easier to fix
Criterion C is hard to improve in a large class, where a teacher cannot read every line of working. In our small batches of four to eight students, teachers review written reasoning closely, so feedback covers presentation as well as accuracy. Our teachers work directly from the MYP rubrics and command terms, which means practice papers are marked in the language the school uses. Weekly worksheets and monthly mocks show whether the habit is changing, and regular parent updates make clear what to work on next. If you are considering our IB MYP tuition programme, this is the kind of feedback you can expect.
Where to start if marks are slipping now
Pick a recent assessment and mark only the communication. Count how many points were lost for missing reasons, missing labels and loose notation. The pattern usually points to one or two habits, and those are the ones to target first. For more practical guides on maths and MYP study habits, visit our blog.
Frequently Asked Questions
What does MYP maths Criterion C assess?
Criterion C assesses how well a student communicates mathematical thinking. That includes using correct notation and terminology, presenting solutions in a logical order, labelling diagrams and graphs, and justifying answers in full sentences where the command term asks for it. It does not reward a correct answer that the reader cannot follow.
Why does my child lose marks in MYP maths even when the answers are right?
Most often the working is missing or hard to follow. Markers need to see method, reasoning and units. A correct final answer with no justification, an unlabelled graph, or an unstated rounding step can each cost marks. Practising written explanations alongside calculations usually closes the gap within a few weeks.
How does INACADEMICS help with Criterion C?
We review written working in small batches of four to eight students, so each student receives feedback on presentation as well as accuracy. Teaching follows the MYP rubrics and command terms, weekly worksheets build the habit, and monthly mocks track progress. Parents receive regular updates measured against the student's plan.
Is free counselling available before enrolling?
Yes. You can call or WhatsApp +91 9014010410, or visit us at 117, 1st Floor, Raichandani Business Bay in Kokapet. The counselling is free and includes a short diagnostic and a per-subject plan, so you can see where marks are being lost before you decide anything.
Criterion C is one of the more rewarding areas to tighten, because the changes often show within a few weeks. If your child's papers keep coming back with the same comments, let us look at them together. Call or WhatsApp +91 9014010410, or send us a message through our contact page, and we will talk through what is costing marks.