Yes, 10 units worth of subjects count towards a student's ATAR. Of those 10 units, at least 2 units of English must count towards the student's ATAR. In the case of a student taking 11 units, there are two possibilities:
- If the 1 unit subject ends up being the student's lowest-performing subject, it will not count towards their ATAR, i.e. the 10 units that will count towards the student's ATAR will consist of 2 units subjects.
- If the 1 unit subject is not the student's lowest performing subject, it will count towards their ATAR. The way that this works is that the student's lowest-performing subject, which in this case would be a 2 unit subject, would count as 1 unit instead of 2, allowing for the 1 unit subject to count (in this case, Mathematics Extension 1). The effect that this has is that the negative effect that unfavourable performance in the 2 unit subject would normally have on the student's ATAR would be halved because the 2 unit subject now only contributes 1 unit towards their ATAR.
We can therefore see the difference between having 1 backup unit compared to having 2 backup units. While the former can reduce the negative impact of unfavourable performance in a 2 unit subject, the latter can completely negate the negative impact that unfavourable performance would have otherwise had on the student's ATAR, which is by replacing the low-performing 2 unit subject with the better-performing, backup 2 unit subject. Of course, it does not necessarily have to be one 2 unit subject. It can be a combination of 1 unit subjects, such as Studies of Religion I.
I hope this helps!
