Secondary 4 is a short year. Schools finish the last chapters in the first months, prelims come in the middle of the year, and the national exams follow soon after. The year-end holidays before Secondary 4 are the last long stretch of time your child has to fix weak Secondary 3 chapters before everything speeds up.
Here is how to use those weeks well for O Level Physics and Chemistry, pure or Combined Science.
A note on the 2027 exams: the SEC
Students in Secondary 3 in 2026 are the first to sit the Singapore-Cambridge Secondary Education Certificate (SEC), which replaces the O Level from 2027. Physics and Chemistry at G3 keep the same mode of assessment, standards and grades (A1 to 9) as the O Level, so the advice here applies in full. Most written papers are taken in one exam period from October, with practicals and other non-written parts before it, and results come out in January.
Why the Secondary 3 chapters matter so much
The national exam papers test the whole syllabus, and a large part of it is taught in Secondary 3. Many Secondary 4 chapters also build on Secondary 3 ones: electricity and electromagnetism build on the basics of current and circuits, and most of Secondary 4 Chemistry needs the mole concept and chemical equations. A gap from Secondary 3 tends to grow in Secondary 4.
The holidays are the best time to close those gaps, because there is no new school content and no weekly tests.
Step 1: find the weak chapters
Start with your child’s end-of-year exam paper. Go through it chapter by chapter and mark where marks were lost. Separate two kinds of mistakes:
- Not understood: your child cannot explain the idea or does not know how to start. These chapters need to be learnt again.
- Understood but careless: wrong units, missing steps, a misread question. These need practice and checking habits, not reteaching.
Step 2: the chapters that most often need work
Physics
- Kinematics: reading and drawing speed-time and distance-time graphs, and finding acceleration and distance from them.
- Turning effects of forces: taking moments about the right point, and explaining stability.
- Pressure: pressure in liquids and the manometer.
- Thermal physics: explaining conduction, convection and radiation in full sentences, which is where many written marks are lost.
Chemistry
- Mole concept: the calculations that the rest of the subject relies on, including limiting reactants and percentage yield.
- Chemical formulae and equations: writing formulae from ions, balancing equations, and ionic equations.
- Acids, bases and salts: choosing the right method to prepare a salt and describing it step by step.
- Qualitative analysis: identifying ions and gases from test results.
Step 3: a six-week holiday plan
About an hour a day, five days a week, is enough. Alternate the two subjects so neither is left for the last week.
- Weeks 1 and 2: relearn. One weak chapter at a time. Read the notes, then write a one-page summary from memory and check it against the notes.
- Weeks 3 and 4: practise by topic. Do questions on each weak chapter until your child can do them without looking at the notes. Topical questions from the Ten Year Series work well here.
- Week 5: written answers. Practise the explain and describe questions, comparing each answer with a mark scheme to see which key points earn the marks.
- Week 6: mixed questions. A few mixed sections from past papers under time, to practise switching between chapters.
Read more about using the O Level Ten Year Series by topic and by year.
Step 4: build the habits that save marks
- Write the formula first, then substitute, then give the answer with its unit.
- In Chemistry, always write state symbols when the question asks for them, and check that every equation is balanced.
- In written answers, use the exact key words from the syllabus. A correct idea in vague words often earns no marks.
- Keep a list of mistakes and look back at it every week.
Pure or Combined Science?
The same plan works for both. Combined Science students take Physics and Chemistry as two parts of one subject, with fewer chapters in each, so the list of weak chapters is usually shorter. Read our guide to pure vs Combined Science.
How we help at Outclass Education
Our Secondary 3 and 4 Physics and Chemistry classes have at most 6 students. Every chapter has our own notes and three Summary Sets of exam-style questions with keyword-marked answers, and the Outclass Learning App gives students quick quizzes and video lessons at home. Parents see what was covered after every lesson in our parent app. See our O Level Physics tuition, O Level Chemistry tuition and Science tuition in Hougang.
Frequently asked questions
When should my child start revising for the Secondary 4 exams?
The year-end holidays before Secondary 4 are the best time to start, by fixing weak Secondary 3 chapters. Full past papers are more useful later, once all the chapters have been taught.
How many hours a day should my child study in the holidays?
About an hour a day for Physics and Chemistry together, five days a week, is enough for most students. Regular short sessions work better than long ones.
Should my child learn Secondary 4 chapters ahead of school?
Only once the Secondary 3 chapters are secure. Most Secondary 4 chapters build on Secondary 3 ones, so fixing those first makes Secondary 4 easier.
Is the plan the same for Combined Science?
Yes. Combined Science has fewer chapters in each subject, so the list of weak chapters is shorter, but the steps are the same.
Next step: Send us an enquiry to book a trial lesson, or WhatsApp us at 9637 2357. We are at 212 Hougang Street 21, a 3-minute walk from Kovan MRT Exit C.
