Subject Combinations – The Most Crucial Choices In Secondary Education

For many years, countless parents who have approached our agency for Secondary Science Tuition wonder why their children are struggling with preparation for O & N Level Science Subjects. It is an undeniable fact that the National O & N Level Exams are an “entrance examination” for a Singaporean Student’s future, but what most of them do not realize is the importance of choosing the right Science combination in Secondary 3. In Secondary 2, every student is briefed about subject combinations at the end of Secondary 2 based on their Examination results. For Science, students have to make a decision of whether to take Biology/Physics/Chemistry and which combination in Combined or Pure Sciences. This is an extremely crucial choice as students will have to stick with the subjects chosen all the way till their National Exams.

Many students are perplexed about choosing the correct subject combinations as they have not had enough exposure to any of the sciences, and also do not know the true weightage of the decision. Hence, most students seek assistance from their school teachers, or Secondary Science Tutors when it comes to making this choice. Here are a few pieces of advice shared by our Secondary Science Tutors for students to make a better decision on their subject combinations.

A secondary science tutor can provide you with good advice to make an informed and reasoned decision

Subject Combinations Will Affect A Student’s Future. It Is Best To Make An Informed & Reasoned Decision

Subject Combination – How It Affects Your Future

The choices for subject combination has a heavy impact on a student’s future education choices. Many students have expressed regret for their hasty subject combination decisions as they realized that they were unable to apply for certain JC Subjects or Polytechnic Courses due to the subjects they had chosen.  For example, at a JC Level, students have a choice of taking H1 or H2 Level of a certain science subject.  However,  The minimum subject requirement for the H2 Science subjects is that the student must achieve B3 and above for the particular Pure Science, or A1 for Combined Sciences. Hence if you were intending to pursue H2 Chemistry or Physics for A Levels, opting to take Combined Sciences at the end of Lower Secondary would not be the best choice. The choices also affect the courses eligible for you in University – For Example, Engineering courses in NUS/NTU/SMU have a minimum requirement of a Pass for O Level Pure Physics or A Level H1 Physics. Hence, the decision made regarding your subject combination at Sec 3 is indeed long-lasting.

Another important point to note is the difference in difficulty between Combined & Pure Sciences.  Combined Sciences is considered as Level 1 Difficulty, which is more of the basic knowledge and concepts, whereas Pure Sciences is at Level 2 Difficulty. However, in JC, H2 Sciences are considered to be of Level 10 Difficulty. At the beginning of JC, students from Combined Sciences will need to put in assiduous effort to chase up to their friends who took Pure Sciences.

Moving On From Lower Secondary Sciences To Upper Secondary Sciences

Students can expect a wider and more in-depth coverage of topics from Lower Secondary Sciences in Upper Secondary. Students are not only required to master the Science subjects,  but also to link the connection between topics and different sciences. Here are some differences pointed out by our Secondary Science Tutors between each Sciences subjects for your reference.


Chemistry is the Science subject which will appear in most subject combinations as it is considered the “Central Science” and can be closely linked to both Biology and Physics. Chemistry is the study of matter and the chemical reactions between substances and matters are anything in the world that takes up space and has mass. In Lower Secondary, the student is introduced to the basics of Chemistry such as learning about Solute and Solvent as well as atoms and molecules. Yet, in Upper Secondary, the student will learn about exothermic and endothermic processes that are covered under the topic of energy changes and enthalpy of reactions.

Secondary science tuition will also inform you about the practical aspects of Secondary School Sciences

Upper Secondary Chemistry Classes Also Have Interesting Practical Lessons Involved!


With Physics, students have to deal with applications in the real world, it focuses on areas such as energy, motion, and the forces of gravity. If you have an interest in space and live an dream of creating a rocket, you may be more inclined towards this subject. In Lower Secondary, you are in contact with Physics in topics like Ray Model of Light and Energy and work done. These topics teach the basics of how light travels and reflections. Whereas in Upper Secondary, you are learning more in-depth in how light refracted in mediums such as water, air, and objects. You will also have to know how will the light bends when travels based on the density of the mediums.


Biology is the study of life and it mainly looking at cells and living organisms. If you aspire to be a Doctor, you should definitely take Biology at the Pure Science level. In Lower Secondary, students are learning topics such as the Human Digestive system and the transport system in living things. In the Digestive system, you are taught what is Digestive system and each function of the body parts, such as the Gall bladder that stores and concentrates bile. In Upper Secondary, Biology no longer looks at how food travels in your body but further into the chemical reaction happening in your body with the food you have eaten.

Here at MindFlex Home Tuition, we have a wide variety of tutors across all 3 Sciences at both the Combined and Pure Sciences Level. If you find yourself in need of academic help, you can find out more about engaging a Secondary Science Tutor from MindFlex Home Tuition with no obligation included.

The Differences Between Combined Sciences And Pure Sciences 

Taking Pure Sciences benefits you if you are looking to pursue GCE ‘A’ Level (Science Course) or Science-related courses in the various Polytechnics in Singapore after your GCE ‘O’ Level. At the end of Secondary 3, MOE Schools often allow Pure Science students a choice to convert to Combined Sciences if they are incapable of coping with studying Pure Sciences. In terms of content coverage, the syllabus content of Combined Sciences are about 75% of Pure Sciences.

The MOE Secondary School Science Syllabus comes with a hands-on and practical examination too. For Triple/ Double Pure Sciences, students will take two/ three separate assessments during curriculum periods, which is known as School-based Science Practical Assessment (SPA). Whereas for Combined Sciences, students will only take one practical assessment under Paper 5 for O Level. Pure Sciences students are graded based on their experimental techniques and their answer scripts, as compared to Combined Sciences where students are graded solely based on their answer scripts.

Double Sciences VS Triple Sciences

Students are only advised to take Triple Sciences if they have obtained a grade of 85% and above for their Sec 2 Sciences. If they do not meet this requirement, they are advised to take Double Sciences. instead. Pure Sciences are extremely difficult and some students who took Triple Sciences are advised to drop to Double Sciences after they have failed Pure Sciences in Secondary 3. Nevertheless, one of the biggest plus points of taking Triple Sciences is that it enables students to have more choices in subjects forming the L1R5 Combination. They will also have wider options when choosing subject combinations at the JC Level, or course choices at the Polytechnic Level. While choosing which Sciences are better for you, it is necessary to look into your interest and future career aspirations. For instance, if you wish to pursue Life Sciences or any Medical Profession, you should consider taking up Pure Biology as one of your Sciences.

On the other hand, if you have a passion for humanities and art subjects, do consider the Double Sciences and Combined Sciences route as they allow students to focus on more Humanities-Based Subjects whilst still having good ground knowledge of Science Concepts. If you are interested, MindFlex Home Tuition also provides Home Tutors for Geography, History, Literature and Social Studies! You may click on the links on each subject to find out more information.

Importance of Scoring Well for Secondary Science

It is needless to say that scoring well for Secondary Science will definitely pull your L1R5/L1R4 scores which is the main deciding academic factor if you are eligible for a particular tertiary institute. On a subject basis, if you are looking to pursue any Engineering Degree courses in NUS, you are required to achieve at least a B or C in H2 Physics/Chemistry for GCE A Level or a pass in O Level in Physics can also be considered. Even with Polytechnic Diploma courses, your Science results will affect your eligibility to enter certain Science related courses. Take the Engineering courses in Singapore Polytechnic as an example, students required to have a pass in at least one of the Pure Sciences (Physics/Chemistry/Biology) or Combined Sciences, to be eligible to enter engineering course. Thus it cannot be stressed enough that students need to score well for Sciences as it really opens up the educational choices available!

Hire a secondary science tutor to help you do well for you o level science subjects

All Science-Related Degree Courses Require Students To Score Well For Their O-Level Science Subjects.

Achieving good results in Science require consistent efforts and strong foundations to understand and apply the concepts learned into solving questions. The topics for each Science are built upon one another and can be linked among themselves. There are a lot of memorization concepts and formulae involved, as well as application-based techniques. If students feel that they are behind or have doubts which they are unable to clarify, we strongly encourage that they seek help as soon as possible from school teachers, or even hiring a home tutor as it is easy for learning gaps to snowball due to the inter-linking of topics.

Here at MindFlex Home Tuition, we provide Top-Quality Science Tutors who are familiar with the Current MOE Syllabus and experienced with teaching Secondary School Students. With Secondary Science Tuition, you can consult your personal tutor for topics that you are uncertain of, especially in Upper Secondary, where classes are taught at a faster pace and teachers hardly have chances to revisit topics that were taught previously. Our Secondary Science Tutors not only help students catch up with learning gaps, but also help create effective study plans to ensure that studying is carried out efficiently. Furthermore, resources specially catered to the O & N Levels will be provided to students to help them further. For example, Mindmaps & Topical Summaries will be provided to help students organize information and internalize them more efficiently.  Question Banks, Timed Practices and Past-Year-Papers will also be provided to make sure that students have adequate practice before attempting the O Level Science Exams. If you are interested to know more about our Secondary Science Tuition, please feel free to click on the following link.

Conclusion – Making An Informed & Reasoned Decision 

Choosing your subject combinations is an important and irreversible decision that will affect both your education and future career. The best piece of advice from our tutors would be that students should choose subject combinations based on their interests and the future courses which they may possibly want to pursue. There is indeed a lot more motivation for students to study hard when students are learning about a subject they are interested in. It is unavoidable that every tough decision often comes with some pros and cons, hence it is important that both parents and students have a good discussion to make an informed and reasoned decision about this important academic choice. If you require any further help, please free to contact us and our friendly team will be more than willing to provide you advice and academic assistance.

If you are interested in more articles related to Secondary School or Science Tuition, here are links to other original articles for you to enjoy:

Secondary Home Tutors – Coping With The Demands of O & N Levels
PSLE Science Tutors – 7 Top PSLE Science Tips from Singapore Tutors
Essential Preparation Guide for JC Chemistry by Top A Level Chemistry Tutors


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