What Do the MYP Science Criteria Actually Mean?

The four MYP Science criteria are separate 0-8 scales the IB uses to judge different skills, not one blended science mark. Criterion A checks your knowledge and how you apply it, B checks how you design an investigation, C checks how you handle data, and D checks how you reflect on science's real-world impact.

They're named Criterion A: Knowing and understanding, Criterion B: Inquiring and designing, Criterion C: Processing and evaluating, and Criterion D: Reflecting on the impacts of science. Every MYP Sciences unit assesses at least two of these four, and most individual tasks target just one or two rather than all four at once.

Each criterion breaks into three or four strands — specific skills marked 0-2 — which add up to that criterion's maximum of 8. Criterion B, for example, has strands covering the problem, the hypothesis, the variables and the overall design, so a weak strand caps your total even if the rest is strong.

No — the same four criteria and command terms apply right across MYP 1 to MYP 5. What changes is task complexity and the achievement-level descriptors: the IB publishes full descriptors for years 1, 3 and 5 as anchor points, and schools interpolate the expectations for years 2 and 4 between them.

Each strand inside a criterion is marked 0-2 against the descriptors in the MYP: Sciences guide, and those strand marks are added together to give that criterion a total out of 8. A task rarely assesses every strand at once, so always check the task-specific clarification to see which ones actually count.

Your school takes your best-fit scores for Criteria A, B, C and D, adds them for a total out of 32, then converts that total using the IB's standard grade-boundary grid into a 1-7 MYP grade. A student sitting on 27/32 can genuinely land on either side of the 6/7 line.

In MYP 1-3, a criterion score of 5-6 out of 8 is a solid, on-track result showing most descriptors are met with only minor gaps. Scores of 7-8 sit at the top achievement band, which is genuinely rare this early — that band is pitched at what a student should reach by MYP 5.

Criterion A rewards explaining scientific ideas accurately and then applying them to a situation you haven't seen in class — not just repeating a definition. The jump from a 3-4 to a 5-6 almost always comes from that second step: applying the concept somewhere new, not describing the familiar example again.

Criterion B marks how well you turn a question into a fair, testable investigation: a hypothesis backed by scientific reasoning, clearly identified variables, and a method detailed enough for someone else to repeat exactly. The mark I dock most often is a hypothesis stated with no reasoning behind it at all.

Criterion C is about your own data — presenting it clearly, interpreting patterns, and judging whether your hypothesis and method actually held up. Criterion D steps outside your experiment entirely, asking you to discuss how science — often someone else's research — affects real people, ethics or the environment.

Criterion D tasks usually ask you to discuss a real issue — antibiotic resistance, renewable energy, gene editing — using accurate scientific vocabulary and properly referenced sources. Read the command term first: 'discuss' wants balanced viewpoints from more than one angle, while 'evaluate' wants you to weigh strengths and weaknesses and reach a judgement.

MYP Sciences uses four skill-based criteria scored out of 8 each, while DP Sciences — Biology, Chemistry and Physics — combines exam papers and an internal assessment into one 1-7 grade with no separate criterion scores reported. Your child's MYP criterion pattern is still a fair signal of which DP level, SL or HL, will suit them best.

Criterion B marks the investigation design, not subject knowledge — so a student who knows the content cold can still score low if the hypothesis lacks reasoning, variables aren't clearly separated, or the method isn't detailed enough to repeat. It's the single most common gap I see between test results and lab report marks.

The most useful resources show model responses marked strand-by-strand, not just content summaries — seeing why a sample answer scored 6 rather than 8 teaches the criteria far faster than a description ever will. Revision Notes and Topical Worksheets organised by criterion, rather than by topic alone, tend to make this clearer for younger MYP students.