What Do the MYP Maths Command Terms Mean?

Command terms are the specific verbs — 'calculate', 'justify', 'investigate' and similar — that tell you exactly what kind of response a question wants. According to the MYP Mathematics guide, first assessed for the current syllabus in 2021, each assessment criterion (A–D) has its own typical set of command terms examiners expect you to respond to precisely.

"Calculate" wants a numerical answer reached through a clear, shown method — the working itself gets marked under Criterion A. "Find" is broader: it can mean solve, identify or determine a value, and doesn't always demand every intermediate step, though showing your process is still the safer habit either way.

"Justify" asks you to give a valid reason, rule or piece of evidence supporting your conclusion — a bare correct answer earns almost no credit against this term. It appears most in Criterion B (Investigating Patterns) and Criterion D tasks, where examiners want to see why your claim is true, not just that it is.

"Describe" wants a detailed account of what happens — a pattern, feature or trend, stated clearly. "Explain" goes further and asks for reasons or a mechanism behind it — why it happens, not just what happens. Confusing the two is one of the most common ways students lose marks in Criterion B write-ups I've marked over the years.

Almost always it's because the command term asked for more than a final number. If a question says "justify" or "explain" and you only wrote the answer, you've technically answered a different question. In fifteen years of marking mock papers, this is the single most common reason a mathematically correct response scores low.

Each of the four MYP Maths criteria leans on particular command terms. Criterion A (Knowing and Understanding) favours 'calculate', 'solve', 'state'. Criterion B (Investigating Patterns) favours 'describe', 'justify', 'verify'. Criterion C (Communicating) uses 'represent' and 'organise'. Criterion D (Applying Mathematics in Real-Life Contexts) leans on 'explain', 'evaluate' and 'interpret'.

"Investigate" means carry out a systematic study — generate several examples, spot a pattern, then test whether the pattern holds. It sits at the heart of Criterion B, and examiners expect you to go beyond one case: try multiple examples, propose a general rule, then justify or verify it algebraically before you finish.

Top marks come from matching your response's depth to what each command term demands — a 'justify' question needs a reasoned argument with evidence, not a number; an 'evaluate' question needs a judgement weighed against alternatives. Quick tip: underline the command term before you write a single digit, every single time.

Many overlap — 'calculate', 'describe' and 'justify' appear in both — but DP Mathematics: Analysis and Approaches and Applications and Interpretation apply a wider glossary at greater depth, including terms like 'deduce' and 'derive'. MYP command terms build the same reasoning skills at a simpler, more scaffolded level.

The list of command terms itself doesn't change between MYP 4 and MYP 5 — it's the same glossary right across MYP 1 to 5. What changes is the complexity of the task attached to each term: a 'justify' question in MYP 5 expects formal algebraic reasoning, where MYP 4 might accept a numerical check of two or three cases.

The full glossary sits inside the MYP Mathematics guide's command terms appendix, published alongside the subject-specific assessment criteria — your maths teacher will have a copy, and many schools display it in the classroom. On RevisionPrep, the MYP Mathematics Revision Notes list every command term next to a worked example matched to its criterion.

Ask your child to explain, out loud, what a command term is actually asking before they start solving — if they can't put it in their own words, they'll likely misjudge how much depth the answer needs. It's a five-minute habit that catches a large share of avoidable mark loss on Criterion B and D tasks.

Because MYP Mathematics assesses the process, not just the outcome — Criterion A explicitly rewards clear, correct method, so an unexplained right answer earns fewer marks than a fully-shown, partly-correct one. It feels harsh at first, but it mirrors exactly how DP Mathematics and university-level maths get marked later on.