Hi Sarah,
It is always good to pick a topic that you are emotionally invested in, so that it makes it easier and more natural to be persuasive. Try thinking through your hobbies and passions and see if there is anything you could write about from these.
Some other topics that I think would work well for persuasive writing would be:
- ethical issues (e.g. abortion, GM technology)
- current political issues (e.g. Australia’s stance on refugees, housing market affordability)
- local community issues (e.g. persuading to build a new park)
- a “this vs this” topic (e.g coffee is better than tea, Marvel is better than DC). This is obviously a simple topic for year 12 level, however, if you have enough substance and argue it very effectively, then it could still be a valuable topic.
Hope this gives you some ideas!