Subject Scaling Guide: How Different Subjects Affect Your ATAR

Subject scaling is one of the most discussed—and most misunderstood—aspects of the ATAR system. Students often hear that certain subjects "scale better" and wonder whether they should choose subjects based on scaling rather than interest. This comprehensive guide explains how scaling works and provides practical advice for making informed subject choices.

What is Subject Scaling?

Subject scaling is a statistical process that adjusts raw subject scores to ensure fair comparisons across different subjects. The fundamental problem scaling solves is this: a mark of 80 in one subject might represent a different level of overall academic ability than a mark of 80 in another subject.

Scaling considers how students in each subject perform across all their other subjects. If students who take Subject A consistently perform very well in all their subjects, this suggests Subject A attracts high-achieving students, and scores in Subject A will scale up. Conversely, if Subject B attracts students with a wider range of abilities, the scaling adjustment will be more moderate.

How Scaling Actually Works

The technical process varies slightly between states, but the principle is consistent. Each year, Tertiary Admission Centres analyse results from every subject and calculate scaling adjustments based on how that year's cohort performed.

Importantly, scaling is not fixed—it changes every year depending on who takes each subject and how they perform. Historical data gives a general indication of scaling patterns, but cannot perfectly predict future outcomes.

Another crucial point: scaling does not create or remove marks from the system. If a subject scales up, it is because students in that subject demonstrated high ability across their studies. If it scales down, students in that subject showed more varied performance overall.

Subjects That Typically Scale Up

Certain subjects consistently scale up because they attract academically strong students who perform well across all their studies:

• Mathematics Extension 2 / Specialist Mathematics: The highest-level mathematics courses consistently scale very well. Students who tackle these challenging subjects typically excel across the board.
• Mathematics Extension 1 / Mathematical Methods: Advanced mathematics subjects that require strong analytical skills. These scale up moderately to significantly.
• Physics: Physics requires strong mathematical ability and logical thinking. It typically attracts students who are strong academically and scales up accordingly.
• Chemistry: A subject requiring strong understanding of concepts and mathematical application. Chemistry generally scales up moderately.
• Economics: Economics requires analytical thinking and often attracts students aiming for competitive courses. It usually scales up slightly.
• Languages: Classical and modern languages (Latin, French, German, Japanese, etc.) often scale well, partly because they require consistent effort and attract dedicated students.

Subjects with Moderate Scaling

Many subjects have scaling adjustments close to neutral or moderate. These include:

• English Advanced: The higher English course scales slightly up in most states
• Biology: A popular science subject with moderate scaling
• History (Modern and Ancient): Humanities subjects with relatively neutral scaling
• Geography: Similar to history with moderate scaling patterns
• Legal Studies: A popular subject with scaling close to neutral
• Business Studies: Common commercial subject with moderate scaling

Subjects That May Scale Down

Some subjects historically scale down slightly. This does not mean these subjects are easier or less valid—it reflects the typical performance patterns of students who choose them:

• Standard English courses (though still essential for ATAR eligibility)
• Some technology and applied subjects
• Some vocational education and training (VET) courses
• General mathematics courses (compared to advanced mathematics)

The Scaling Trap to Avoid

Here is the most important advice about scaling: do not choose subjects purely for scaling benefits. This strategy often backfires for several reasons:

First, if you struggle in a high-scaling subject and achieve a low raw mark, that low mark after scaling will still hurt your ATAR more than a higher mark in a lower-scaling subject. A mark of 60 in Specialist Maths, even scaled up, may contribute less than a mark of 90 in a moderately-scaling subject.

Second, studying subjects you dislike or find extremely difficult is demoralising and can affect your performance across all subjects. Year 12 is demanding enough without adding unnecessary stress.

Third, university courses have prerequisites. There is no point chasing scaling in Physics if you need Drama for your preferred performing arts course.

Smart Subject Selection Strategies

Instead of chasing scaling, follow these principles for subject selection:

• Choose subjects you enjoy: You will study these subjects for two years. Interest sustains motivation through challenging periods.
• Consider your strengths: You will likely perform better in subjects that match your natural abilities. This strong performance matters more than scaling adjustments.
• Check prerequisites: Ensure you meet requirements for courses you might want to study at university. Prerequisites are non-negotiable.
• Maintain balance: A mix of subject types (sciences, humanities, creative) often works well for both ATAR and university preparation.
• Seek advice: Talk to teachers, career counsellors, and students who have taken subjects you are considering.

Using Our Calculator for Planning

Our free ATAR calculator includes approximate scaling factors for common subjects in each state. Use it to explore how different subject combinations might affect your estimated ATAR. Try entering realistic expected scores for subjects you enjoy versus subjects chosen for scaling—you may find the results surprising.

Remember that the calculator provides estimates based on simplified models. Actual scaling depends on each year's specific cohort and results.

Conclusion

Subject scaling is an important part of how ATAR is calculated, designed to ensure fair comparisons across different subjects. However, chasing scaling benefits at the expense of interest and ability is rarely a good strategy. Choose subjects you enjoy, where you can achieve your best results, that meet any prerequisites you need, and trust that strong performance will translate into a strong ATAR regardless of scaling minutiae.