I'm not saying an exam for citizenship.
Here in the US we've got a Congressionally-funded civics education program that's available for a large majority of high school students in their final year. Making classes like that mandatory for graduation would be a good first step.
And maybe a couple of history or economics classes to help people determine the difference between communism, socialism, social democracy, democratic socialism, capitalism, fascism, et al. so that people don't blindly follow what a politician says. If we depend on political parties or mommy/daddy to teach kids about how politics works, we're never going to break the Cold War mindset here in the US.
I'm just tired of my comparatively-informed vote being overridden by some idiot who doesn't know the difference between the three branches of government and votes for a party just because daddy did. Unfortunately...there's a lot of people like that in this country. That's not a democracy--that's rule by the idiots.