Singapore Biology Olympiad Past Papers May 2026

Do not just "do the paper and check answers." That wastes the paper.

For every question you got wrong or guessed:

Q24 (SBO 2019): Why do C4 plants have higher water use efficiency than C3 plants? Answer: Because PEP carboxylase has higher affinity for CO2, allowing stomata to remain partially closed. Source: Raven Biology of Plants, Ch. 8.

| Week | Focus | Activity | | :--- | :--- | :--- | | 1 | Baseline | Take oldest available paper (e.g., SBO 2015). Score it. List bottom 3 topics. | | 2 | Cell & Genetics | Study gaps. Take Cell & Genetics sections only from another paper. | | 3 | Physiology | Study gaps (Taiz & Guyton). Take Physiology sections from a third paper. | | 4 | Ecology & Evolution | Study gaps (Ricklefs). Take Ecology & Evolution sections. | | 5 | Full Mock | Take a recent paper (e.g., SBO 2022). Strict timing. | | 6 | Final review | Review only your Missed Concept Cards. Do 50 random questions from any paper. |

Question: "A student measures oxygen production in spinach discs. What is the control?" singapore biology olympiad past papers

For every mistake, ask:

Q: Are SBO past papers available for free online? A: Full official PDFs are rarely free due to copyright. However, the IBO archives (free) and snippets posted by NUS High School on their "SBO Resources" page are legal and free.

Q: Should I use 'O' Level Biology past papers instead? A: No. That is like training for a marathon by walking to the kitchen. 'O' Level papers are too shallow. Use A-Level H2 Biology papers as a baseline first, then move to SBO.

Q: How many years of past papers should I solve? A: 5 years minimum. 10 years (2014–2023) is the gold standard. Patterns repeat every 4-5 years. Do not just "do the paper and check answers

Q: What if I cannot solve a question? A: Use the "Three-Pass Rule":

The answer is often the most specific correct statement. SBO examiners dislike vague, textbook-generic answers. When reviewing a past paper, ask: "Why is option B more precise than option C?"

If you can explain that for 80% of the paper, you are likely in the top 10% of Singapore. Good luck.

Finding official Singapore Biology Olympiad (SBO) past papers is notoriously difficult because organizers maintain a strict non-disclosure policy for local rounds. However, the International Biology Olympiad (IBO) archive remains the "gold standard" for practice, as it provides the foundation for the most challenging questions in the Singapore competition. Top Resources for Past Papers & Practice Q24 (SBO 2019): Why do C4 plants have

International Biology Olympiad (IBO) Archive: This is the most critical resource for SBO candidates. It contains an extensive collection of theoretical and practical papers with official answer keys, including recent sets from 2022.

Biolympiads.com Past Papers Gallery: A helpful hub that categorizes various international papers into manageable "Sample Questions" rounds, making it easier to structure your practice sessions.

Scribd IBO Collection (1990-2013): A large PDF archive of legacy papers that are excellent for building foundational conceptual knowledge. Core Preparation Strategies Singapore Junior Biology Olympiad (SJBO) - Biolympiads

Round 2: Practical * Cell & Molecular Biology. * Plant Anatomy. * Animal Anatomy. * Physiology & Morphology. * Ecology & Ethology. Biolympiads Olympiad experience - NUSHSCollegeTalk Test