@James51 and originality
The NAPLAN test is the worst sort of high stakes testing. Writing a essay outside of the standard criteria will --- even with humans marking --- get you poor results as it won't fit within the marking rubrics. These rubrics -- 'marking criteria' would be the less jargon phrase -- are designed to allow no scope for creativity. As a trivial example of creativity: if you gave the answer as a poem that would garner no additional marks and would threaten the marks allowed for grammar and spelling.
The NAPLAN system is gamed by schools, with weeks of "teaching to the test" being commonplace. Although the government denies it, the NAPLAN preparation constrains the time available for actual teaching of material. In particular the Year 9 NAPLAN falls exactly when algebra is being taught and at a recent corridor chat at a teaching conference there was consensus that there was a fall in student ability in basic symbolic manipulation because NAPLAN has vacuumed time away from that foundation skill.
The government denies the tests are high stakes. But in reality they gateway admission to all advanced programmes. Even for trades programmes oversubscribed programmes are often determined by NAPLAN ranking -- why wouldn't you drag up your school's average given the opportunity?