IB MYP Sciences: The Four Assessment Criteria in Practice -- Practice Questions

These are original questions written for Marlbridge, modelling the kind of evidence-evaluation judgment MYP Sciences’s assessment actually requires. They are not reproduced IB material – the IB holds copyright in its own subject guides and exemplars. Use these alongside official exemplars available through your school.

Related: Criteria in Practice study guide and revision notes.

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Section A

1. Name the four assessment criteria for MYP Sciences. [4]

2. Do the four criteria’s descriptors differ between a discrete-model course and an integrated-model course? [1]

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Section B

3. Asked why a metal spoon feels colder than a wooden spoon at the same room temperature, a student answers: “Metal has higher thermal conductivity than wood.”

(a) Explain why this answer alone does not demonstrate top-band Criterion A evidence. [2] (b) Describe what would need to be added. [3]

4. A student is given a fixed worksheet procedure to measure how temperature affects reaction rate, follows it exactly, and records the results.

(a) Explain why this task, completed exactly as given, is unlikely to generate top-band Criterion B evidence on its own. [3] (b) Describe what the student would need to add to move toward top-band evidence. [3]

5. A student’s evaluation of their reaction-rate investigation states: “A limitation of this experiment is that errors could have occurred. To improve it, we could use more trials.”

(a) Explain why this evaluation is unlikely to reach top band on Criterion C. [3] (b) Rewrite it in outline to reflect what top-band evidence would include instead. [3]

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Section C

6. A student’s Criterion D response on genetically modified crops states only: “GM crops increase yield and help feed more people, so they are a positive development for agriculture.” Explain what is missing relative to top-band Criterion D evidence, and rewrite the response in outline to fix it. [6]

7. Explain why a single well-designed practical investigation can generate evidence for all four assessment criteria at once, using a specific example investigation to illustrate how each criterion’s evidence would emerge from it. [8]

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Worked answers

1. Knowing and understanding (A), Inquiring and designing (B), Processing and evaluating (C), Reflecting on the impacts of science (D). [4]

2. No – the four criteria’s descriptors stay identical regardless of course model; only the specific scientific content an investigation draws on changes. [1]

3. (a) This answer names the relevant concept (thermal conductivity) but does not apply it to reach and justify a scientifically supported judgment – it does not explain the mechanism (why higher conductivity means faster heat transfer away from the hand) or connect this to the distinction between actual and perceived temperature, which is what the question is really asking about. [2] (b) The student would need to explain that because metal has a higher thermal conductivity, heat transfers away from the hand into the metal faster than into the wood, so the hand loses heat more rapidly when touching the metal spoon – and use this reasoning to state explicitly that both spoons are at the identical actual temperature, but the metal spoon feels colder because of how quickly it conducts heat away from the skin, not because it is genuinely colder. [3]

4. (a) Top-band Criterion B evidence requires the student to formulate their own testable research question and hypothesis, identify and justify variables to control, and justify their chosen method. Simply following a prescribed worksheet procedure exactly as given demonstrates the ability to carry out an investigation, but not the independent inquiry and design skill the criterion is specifically built to assess. [3] (b) The student would need to go beyond the given procedure – for example, proposing their own specific, testable research question (such as how a particular reactant’s concentration affects reaction rate under otherwise controlled conditions), explicitly justifying which variables need to be controlled and why, and explaining the reasoning behind the chosen method, rather than treating the worksheet’s instructions as the investigation’s design. [3]

5. (a) Top-band Criterion C evidence requires identifying a specific limitation of the actual method used and proposing a specific, targeted improvement – “errors could have occurred” and “use more trials” are both generic statements that could apply to virtually any experiment, and do not demonstrate genuine evaluation of this specific investigation’s actual method. [3] (b) A stronger version might read: “A limitation of this experiment is that the reaction’s endpoint was judged by eye, watching for a colour change, which introduces timing error since different observers (or the same observer at different times) may judge the exact moment of colour change slightly differently. A specific improvement would be to use a colorimeter to detect the reaction’s endpoint automatically and objectively, removing this source of human judgment error from the timing measurement.” This identifies a specific, method-specific limitation and a correspondingly specific, targeted improvement, rather than generic statements that could apply to any investigation. [3]

6. Top-band Criterion D evidence requires a genuine, two-sided evaluation – presenting both a real benefit and a real limitation or risk, properly sourced where relevant, and reaching a reasoned judgment. The given response presents only a benefit (increased yield) and states a conclusion (a “positive development”) without ever considering a genuine limitation or risk, or citing any source for its claims. A stronger version might read: “GM crops have been shown to increase yield under specific growing conditions [citation], which can contribute to food security in regions facing agricultural pressure. However, published sources have also raised ecological concerns, such as the potential for reduced biodiversity around GM crop monocultures, and economic concerns about smallholder farmers’ dependence on seed suppliers [citation]. Weighing these considerations, GM crops appear to offer meaningful benefits in specific contexts, but their wider adoption raises genuine trade-offs that are not fully captured by yield figures alone.” This presents both sides with sourcing, and reaches a reasoned, qualified judgment rather than a one-sided conclusion. [6]

7. Consider an investigation into how light intensity affects the rate of photosynthesis in an aquatic plant. Criterion A evidence emerges from the scientific knowledge underpinning the investigation – understanding and applying the concept that photosynthesis rate depends on light availability up to a saturation point, used to predict and interpret the expected pattern. Criterion B evidence emerges from designing the investigation itself – formulating a specific testable question (how does light intensity affect the rate of oxygen bubble production), identifying variables to control (water temperature, carbon dioxide availability, plant size), and justifying the chosen method for varying and measuring light intensity. Criterion C evidence emerges from processing and evaluating the resulting data – graphing bubble-production rate against light intensity, identifying the trend (including any levelling-off at high intensities), and evaluating a specific limitation of the method (for example, difficulty counting bubbles accurately at high production rates) with a specific improvement (using a gas syringe to measure volume instead of counting bubbles). Criterion D evidence emerges, where the task calls for it, from reflecting on the investigation’s broader significance – for example, connecting the findings to real-world applications such as optimising light conditions in commercial aquaculture or greenhouse agriculture, evaluating both benefits and limitations of applying laboratory findings to a real-world context. All four criteria’s evidence arises from the same single, connected piece of investigative work, rather than requiring four separate, unrelated tasks. [8]

Official syllabus

International Baccalaureate Organization, Middle Years Programme Subject Brief – Sciences, from 2014, (c) 2015 – the same source cited by the study guide and revision notes. Verified 2026-09-06.