When it comes to PSLE Science, students often struggle with topics that are either highly complex, or require multiple Science concepts to be juggled at once. In order to excel in their PSLE Science paper, students need to get plenty of practice with the tougher parts of the syllabus.
In this article, Keynote Learning goes through some of the challenging questions that students have faced in previous exams, and provides a handy guide to solving them!
Q1: Heat Conductivity and Turkey (2022)
This question from the 2022 PSLE Science Booklet B left many students stumped. While part (a) served as a simple thermometer reading question, part (b) asked them to explain why a cold turkey did not reach the same temperature of the oven (160 degrees) after 2 hours.
What Made This Question Challenging?
Many students were not able to identify the intended answer by reading the question text directly. Due to the extremely open-ended nature of part (b), students were missing key terms such as 'Poor conductor of heat' and 'heat transfer' that would normally help them identify the topic they were meant to explain.
How Can Students Solve These Questions?
In order for a Primary School Student to solve this question, they need to exercise critical thinking and recognise which part of the PSLE Science Syllabus is being tested. Once they read the segment of the question that mentions temperature and time, they should learn to identify that the question is about heat conduction and work through the following points:
From there, they simply need to use proper answering techniques and put these insights into complete sentences that include relevant terms. A model answer would be:
As turkey is a poor conductor of heat, heat from the surface of the turkey will be transferred / conducted to the inside of the turkey slowly.
Q2: Mosquito Life Cycles + Waste (2022)
This next question, also in the 2022 paper, tested two scientific concepts at once: The Life cycles of animals, and Living together. It consisted of four questions of equal mark weightage, requiring the student to master all of them.
What Made This Question Challenging?
The most difficult parts of the question were parts (b) and (d).
Part (b) was confusing, as many students would automatically make this incorrect connection:
However, 'respiration' would be wrong, as it does not answer the question.
Part (d) was also difficult for students, as they would often make a sensible assumption that the trap was meant to suffocate the mosquitoes. A possible explanation is that the mosquitoes would consume the oxygen in the trap, inhale the carbon dioxide, and die.
Additionally, students might have thought that the mosquitoes would die due to the lack of food. But because of the emphasis on the word 'quickly', starvation was not an acceptable answer.
As for part (a) and (c), the answers were relatively simple, but required students to remember the needs of living things and concepts learnt in the chapter of Living Together. The mosquitoes were attracted to the stagnant water, which they require as part of their life cycle, and were attracted to the human waste as it had nutrients for their larvae. The presence of the tube allowed them to detect the waste, and thus attracted them into the trap to lay their eggs.
How Can Students Solve These Questions?
Such questions are tough due to the large number of factors that students need to consider at once. They need to be able to identify and avoid trick questions and read every part of the text. Here's a detailed breakdown:
For this question in particular, the important keywords were hidden in the diagrams and wording. In order to solve this question, students had to pay attention to the various conditions that were being set. Missing out on several keywords could cause the answer to change significantly.
The specific keyword of question (b) is: Gases are given out by waste. Thus, this means that the only acceptable process is decomposition, with the correct organisms being bacteria or decomposers.
The two key parts of question D are that the trap allows air to enter and that the mosquitoes die quickly. This means that there is gas exchange, and the mosquitoes are able to carry out respiration. Instead, the important part of the figure is the clear plastic dome, and the sun present in the first diagram. With these two pieces of information, students would be able to conclude that the mosquitoes would overheat due to the sunlight and die, rather than suffocate.
Rote memorisation does not help with these types of questions, and students need to be able to carry out reasoning and apply logic to their answers, with the help of the keywords in the question text.
Q3: Life Cycles of Animals + Eggshell (2024)
This 2024 question tested students on the life cycles of animals. As a three-part question, it required students to make inferences and carry out reasoning based on the information given.
Part (a) of the question was simple, and was simply a graph-reading exercise that stated that an animal's eggshell was thinned by exposure to substance X. Part (b) was where students needed to carry out logical deductions based on the question.
Part (c) was also a chart reading exercise, that showed the ratio of male and female animals hatched from an egg. At a lower temperature, all offspring were female, while at higher temperatures, all offspring were male.
What Made This Question Challenging?
Some students found part (c) of this question tricky, as they were not able to draw a connection between the temperature of the animal's eggs and the 'continuity of its kind'
How Can Students Solve These Questions?
These questions involve imagining how an animal lives its life and responds to stimulus.
Section (b) asked how substance X helped a developing animal Y. The answer is that a thinner shell makes it easier for the animal to hatch, giving the offspring a higher chance of survival.
The secret behind part (c) was the fact that animals require both male and females in order to survive. Therefore, at 32 degrees, there is an even ratio of sexes being born. This helps maintain an animal's population, and aids in the continuation of their species.
Q4: Life Cycles of Animals + Mosquitoes (2020)
Another mosquito question challenged students in a previous paper. This question was separated into part (a) and (b), with (b) having three sub-questions. It covered life cycles again, with emphasis on mosquito larvae, as well as a second half that covered experimentation with Malaria.
What Made This Question Challenging?
This question was challenging to most students as many parts did not have obvious scientific principles linked to them. In fact, some sections had simple common sense solutions, which might have caused students to overthink.
How Can Students Solve These Questions?
Part (a) was a simple question on mosquito larvae, with the answer being that the oil prevents larvae from breathing, and kills them through suffocation.
Part (b) was significantly more complicated. The vital keywords behind these tricky questions were: 'children infected with malaria are found to be bitten more often by mosquito a'. The main topic was to distinguish how mosquitoes behave in the presence of infected children, compared to uninfected children.
Part (i) was a hypothesis question. As the text has provided the information that mosquitoes are more likely to bite infected children, the student should come up with the following reasoning for their hypothesis, and write it out:
Part (ii) is deceptively simple, and barely requires a student to think. The tricky part of this question is the risk of overthinking and trying to include some sort of key concept into it. The answer is simply: It is easier to collect data on how many mosquitoes land on the shirt if it is white, as they are more visible on a light surface as mosquitos are black.
Lastly, (iii) is a similar principle to the mosquito and human waste question. The smell can be used to attract mosquitoes into a trap, in order to eliminate them and reduce the spread of Malaria.
Q5: Electric Currents + Force (2022)
This question involved electrical circuits. Students needed to learn to read the electric diagrams and understand them, as well as work out how changing parts will affect the setup.
What Made This Question Challenging?
This required answer is extremely long for PSLE standards, hence the amount of space given, and students need to utilise proper answering techniques instead of just Science knowledge. The setup is also complex for Primary School standards, and they may not understand that every single connected object in the diagram is conductive, and is thus part of the circuit.
How Can Students Solve These Questions?
Firstly, questions on electrical systems can be resolved by identifying the key parts of the circuit and what the device is meant to achieve. For example, students should open by noticing the battery, the switch, and the presence of magnets. They should then imagine how the magnets will be moving once the switch is turned on.
Doing this, along with reading the question, will allow them to realise that the whole setup is magnetic. They should then analyse how it will move when the switch is activated. An important skill is imagining how the setup will move in physical space.
By following this line of logic, students will be able to understand why the apparatus repeatedly strikes the bell. The circuit is being opened and closed repeatedly, causing a physical motion that resets itself for future rings.
Acing the PSLE Science Examination With Keynote Learning
Difficult questions like these can stump a student and cause them to lose precious marks. In order to avoid this, it is important for students to build a solid foundation, and become familiar with all commonly tested topics.
At Keynote Learning, we treat education as more than a means to an end. We strive to make learning a fruitful journey with the help of our experienced teachers, who focus on teaching your giving your child the critical thinking skills, problem-solving skills, and the confidence needed to score well in their Science exams!
We provide:
Through these methods, we aim to help every student become a self-directed learner, and ensure that they're able to take control of their education. Whether they're looking for clarification on tough concepts, step-by-step support for their Science homework, or simply better resources to revise effectively, Keynote Learning is here to guide them every step of the way.