Here's another crazy idea for you guys to rip apart (bear with me, Ambien Walrus is coming and I have to finish before he gets to my computer desk):
Instead of making firearms illegal, lets require all citizens to go through firearms safety courses. I separated this sentence out because I mean all citizens. It can be incorporated at the High School level, lower grades would work for some communities. Adults can go to training facilities of their choosing.
Out in Colorado you were required to take a hunter safety course to buy a tag. I assume those courses still exist. If they don't-bring them back, if they do-use them.
You can start with a basic safety class that everyone has to take, and then have a system set up to cover weapons/weapon types for if/when the citizen decides to make a purchase, giving a more focused and specific curriculum. Let the classes be set up as a joint project between the NRA and Homeland security. Allow weapon permits based on class performance. That is, you have to show some proficiency to purchase the weapon, with a bit of tactical/strategic theory thrown in to help you defend yourself if necessary.
At no point am I suggesting that those people who own guns now would have to attend these classes to keep their weapons. The NRA would jump all over setting this up.