ICAS Science vs Big Science Competition: Which Is Better For Your Child?
ICAS Science and Big Science Competition both help students practise science reasoning, but they are not the same. ICAS is a broader academic assessment brand across subjects. Big Science is a science competition run with a strong emphasis on scientific thinking and real-world application.
For families, the better question is not which one is "better". The better question is what each exam tells you about the student.
What ICAS Science Is Useful For
ICAS Science is useful when parents want an external academic benchmark. It can show how a student handles school-aligned science reasoning compared with a wider cohort.
ICAS preparation should focus on:
- reading the question carefully;
- applying science concepts in context;
- interpreting diagrams, tables and short passages;
- avoiding overcomplicated answers.
What Big Science Is Useful For
Big Science is useful as an enrichment and diagnostic competition for Years 7-10. It can help students practise scientific literacy, data reasoning and application beyond routine class questions.
Big Science preparation should focus on:
- broad science foundations;
- graph and experiment interpretation;
- cause-and-effect reasoning;
- applying concepts to unfamiliar scenarios.
Which Should Come First?
If the student is new to competitions, either can be a good start. Choose ICAS if the family wants a broad academic assessment across subjects. Choose Big Science if the priority is science enrichment and a possible pathway toward JSO.
For a student aiming at Junior Science Olympiad later, Big Science often gives a cleaner science-specific diagnostic.
Preparation Overlap
There is strong overlap:
- scientific vocabulary;
- reading comprehension;
- experimental design;
- data interpretation;
- application of biology, chemistry, physics and Earth science ideas.
The difference is emphasis. ICAS often feels closer to broad academic assessment. Big Science is more clearly positioned as science competition enrichment.
How To Use The Exam Guides
This article explains how the two assessments differ. For practical details such as current dates, sitting windows, year levels and format, use the individual exam guides:
Free And Helpful Preparation Resources
ICAS Science and Big Science overlap in science reasoning, but the best preparation resources are not identical. ICAS is closer to broad academic assessment, while Big Science is more directly science competition oriented.
Here are five useful starting points:
| Resource | Best for | Notes |
|---|---|---|
| ICAS official preparation tools and sample tests | Understanding ICAS question style | Use the free sample material first; some official practice products may be paid. |
| Australian Science Innovations Big Science page | Understanding Big Science format and purpose | Best source for official Big Science organiser information. |
| ABC Education Science | General Australian science revision | Useful for rebuilding school science concepts before assessment-style questions. |
| Science by Doing or Science Connections | Curriculum-aligned science learning | Useful for experiments, topic understanding and scientific literacy. |
| AceAchievers ICAS Science, Big Science and JSO exam guides | Parent-friendly planning | Useful for comparing ICAS, Big Science and possible next steps into JSO. |
FAQ
Is Big Science harder than ICAS Science?
Difficulty depends on year level and student strengths. Big Science often feels more science-competition focused, while ICAS Science feels more like a broad academic assessment.
Can my child do both ICAS Science and Big Science?
Yes. Many students can benefit from both, especially if they use each result to identify different strengths and gaps.
Which is better for Junior Science Olympiad preparation?
Big Science is usually the clearer stepping stone because it focuses on science enrichment and reasoning.
How should students prepare for both?
Build broad science foundations, practise data interpretation and review mistakes carefully after every practice set.