Your child studies. They understand the topic. And Section B still takes 8–10 marks off them. Here's what's actually going on — and what fixes it.
After years of marking primary science scripts, I can tell you the uncomfortable truth: most marks lost in PSLE Science open-ended questions have nothing to do with knowledge gaps. The student knew the science. The answer just wasn't written in a way the marking scheme could reward. These are the five patterns I see over and over.
PSLE Science open-ended answers are marked against specific keywords and phrases. A student can describe a concept perfectly in their own words and still score zero, because the marker is looking for terms like "gain/lose heat", "water vapour condenses", or "less water is lost through the leaves" — not a loose paraphrase.
The fix: learn the keyword patterns topic by topic. For every common question type there is a reliable answer structure, and once a student has it, the same 2 marks stop leaking on every paper.
A question asks "Explain why the water level in the container decreased." The student writes everything they know about evaporation — the definition, the factors, the water cycle. The one thing missing? The direct link back to this container, this experiment, this water level. Markers award marks for application, not recitation.
The fix: every answer must name the objects in the question. Train the habit of ending with a phrase that ties the science back to the exact scenario asked.
Two-mark questions usually want a complete causal chain: what happened, and what it led to. Students often give only one half — "the ice melted" — without the second — "because it gained heat from the surroundings." Half a chain earns half the marks at best.
The fix: the "because → therefore" check. Before moving on, the student asks: did I state the cause AND the effect? If a 2-mark question got a one-clause answer, something is missing.
Questions about fair tests, reliability, and aims trip up even strong students. Answers about the aim of an experiment must mention the changed variable and the measured variable. Answers about reliability must mention repeating and averaging. Miss the framework, and the marks are gone regardless of how sensible the answer sounds.
The fix: memorise the three experiment answer frames — aim, fair test, reliability. They are almost fill-in-the-blank once learned, and they appear in nearly every prelim paper in Singapore.
Section B sits at the end of the paper, exactly when students are tired and rushing. Answers shrink to fragments, keywords get skipped, and questions get misread. A student who would score 4/5 on a topic at home scores 2/5 in the hall — purely from exam-condition decay.
The fix: timed drills under real conditions, with a fixed time budget per question. Speed with structure is a trainable skill, and it's often the fastest 5–8 marks a P6 student can recover.
The pattern behind all five: these are answering-technique problems, not intelligence problems. That's why scores can move fast once the technique is fixed — my students have gone from 35% to 88% in four months without becoming "smarter." They simply stopped giving marks away.
If this sounds like your child — understands the work, loses the marks — send me their latest Science paper on WhatsApp. I'll point out exactly which of these five leaks is costing them, free, before you decide anything about tuition.
PSLE Science · P5–P6
Small live online classes, taught personally by Mr Yeo, built around the keyword answering method in this guide.
See the Science programme →