My lad teaches SOSE (Study of Society and Environment) so politics comes into it a bit. He has to be careful what he says, so he teaches them to deconstruct the bullshit they hear and see on the various media, particularly TV. They watch a news program from the night before, which he's recorded from commercial TV, then go through it and 'translate' it into the real facts, often realising in the process that the truth is far from what is being presented.
He says he finds many pupils, who are aged 15-18 as he teaches grades 10-12, become far more left wing in this process. Our commercial media is extremely right wing, being owned mainly by the loathsome Rupert Murdoch. Some parents don't like it, but he never pushes one political party - he simply teaches the kids to watch and analyse. Other parents absolutely love it, and say the TV news is fun at home now, as their kids deconstruct the news with hilarious results.
Of course, this being Australia, once they turn 18 they are required by law to turn up to a polling station and put in a ballot paper (which they could spoil or leave blank if they want, of course).