The O/L Science paper is on Wednesday, 16 December 2026. Counting back from that day gives eight weeks, and this plan fills them with the topics that actually repeat in 13 past Paper I sittings (2013 to 2025), not with the whole syllabus in textbook order.
- Paper II, 08:30 – 11:40
- Paper I (MCQ), 13:00 – 14:00
The eight weeks at a glance
| Week | Focus |
|---|---|
| 121 Oct – 27 Oct | Physics |
| 228 Oct – 3 Nov | Biology |
| 34 Nov – 10 Nov | Chemistry |
| 411 Nov – 17 Nov | Environment and Earth, plus your weakest area |
| 518 Nov – 24 Nov | The hardest topics |
| 625 Nov – 1 Dec | Your own wrong-answer list |
| 72 Dec – 8 Dec | Full papers, timed |
| 89 Dec – 15 Dec | Wrong answers only, then rest |
Weeks 1 to 4: the topics that repeat
Science topic tags are fine-grained, so the weeks are split by area of the syllabus. Each list shows the topics in that area with the most past-paper questions. Each day: twenty past-paper questions from that week's topics, then read the explanation of every one you missed.
- ආලෝක වර්තනය · 3 of 13 years, 3 questions
- තරල පීඩනය · 3 of 13 years, 3 questions
- ප්‍රවේග-කාල ප්‍රස්තාර · 3 of 13 years, 3 questions
- විද්‍යුත් චුම්බක ප්‍රේරණය · 3 of 13 years, 3 questions
- සම්ප්‍රයුක්ත බලය · 3 of 13 years, 3 questions
- අර්ධ සන්නායක · 2 of 13 years, 2 questions
- උෂ්ණත්ව පරිමාණ පරිවර්තනය · 2 of 13 years, 2 questions
- ඝර්ෂණ බලය · 2 of 13 years, 2 questions
- ප්‍රභාසංශ්ලේෂණය · 6 of 13 years, 7 questions
- ප්‍රවේණික ආබාධ · 3 of 13 years, 4 questions
- ද්විපද නාමකරණය · 3 of 13 years, 3 questions
- පාරිසරික පිරමිඩ · 3 of 13 years, 3 questions
- බහිස්ස්‍රාවය · 3 of 13 years, 3 questions
- සෛල ඉන්ද්‍රියිකා · 3 of 13 years, 3 questions
- ජීවීන් වර්ගීකරණය · 2 of 13 years, 2 questions
- ජෛව අණු · 2 of 13 years, 2 questions
- මවුල සංකල්පය · 5 of 13 years, 5 questions
- වෙන් කිරීමේ ක්‍රම · 3 of 13 years, 3 questions
- සහසංයුජ බන්ධන · 3 of 13 years, 3 questions
- අම්ල උදාසීන කිරීම · 2 of 13 years, 2 questions
- ප්‍රතික්‍රියා වේගයට බලපාන සාධක · 2 of 13 years, 2 questions
- මවුල භාගය · 2 of 13 years, 2 questions
- මවුල සංකල්පය - පරමාණු ගණන් කිරීම · 2 of 13 years, 2 questions
- මූලද්‍රව්‍යවල ගුණ · 2 of 13 years, 2 questions
- ලෝක විද්‍යා දිනය · 2 of 13 years, 2 questions
- අපද්‍රව්‍ය කලමනාකරණය · 1 of 13 years, 1 questions
- අපද්‍රව්‍ය කළමනාකරණය - 3R මූලධර්ම · 1 of 13 years, 1 questions
- අපද්‍රව්‍ය කළමනාකරණය (3R) · 1 of 13 years, 1 questions
- ආපදා හා මිනිස් බලපෑම · 1 of 13 years, 1 questions
- ආලෝකකරණ උපකරණ හා පාරිසරික දූෂණය · 1 of 13 years, 1 questions
- ආහාර පිසීමේ උපකරණ හා ගෘහස්ථ වායු දූෂණය · 1 of 13 years, 1 questions
- ආහාර සැතපුම් · 1 of 13 years, 1 questions
Week 5: the hardest topics
These are the topics where the largest share of past questions is rated hard by our curators. A week on them, after the core is in place, is the cheapest way to lift a good score to a very good one.
- ලෝක විද්‍යා දිනය · 2 of 2 questions rated hard
- විද්‍යුත් පරිපථ · 2 of 2 questions rated hard
- විද්‍යුත් රසායනික කෝෂයේ ඉලෙක්ට්‍රෝඩ ප්‍රතික්‍රියා · 2 of 2 questions rated hard
- පාරිසරික පිරමිඩ · 2 of 3 questions rated hard
- සහසංයුජ බන්ධන · 2 of 3 questions rated hard
- ප්‍රවේණික ආබාධ · 2 of 4 questions rated hard
The reasons, with worked questions, are in the hardest O/L Science MCQ topics.
Weeks 6 to 8: from your mistakes to the paper
- Week 6: no new questions. Go back through every question you got wrong in weeks 1 to 5 and answer them again until each one is right twice.
- Week 7: two full Paper I papers on the clock, from years you have not done yet. Mark them, and add every miss to the list.
- Week 8: the list, one last time, and sleep. Nothing new in the last three days; the paper-day guide has what to do on each of them.
Three things specific to Science
- Calculators are not allowed in any O/L paper this year. Every mole, pressure, density and speed calculation you practise from now on, do it by hand.
- About a quarter of Paper I questions lean on a diagram, graph or table. When you revise a topic, redraw its standard diagram from memory once.
- Biology, chemistry and physics carry roughly equal shares of the paper. Do not drop a whole area because it is your weakest: a third of the marks live there.
Started late? Keep the order and squeeze it: weeks 1 to 4 become one topic set every three or four days, and never skip the wrong-answer list. The list is the plan.
A question from week 1, to start today
කොපුල් සෛල ආලෝක අණ්වීක්ෂය යටතේ නිරීක්ෂණය කළ විට දැකිය හැකි ඉන්ද්‍රියිකාවක් වන්නේ
- Aගොල්ගි සංකීර්ණය ය.
- Bමයිටොකොන්ඩ්‍රියම ය.
- Cන්‍යෂ්ටිය ය.
- Dරයිබොසෝම ය.