I have 3 children, ages 6 1/2, 5, and 3 1/2. (And another due in Dec.)
I keep my knives and my sword IN reach of all of them. They know that they are not to be touched without asking.
When we go out on to the property to hike, hunt, or garden, they are each allowed to carry one of my knives, but they know that they are not to use them unless I say so.
My youngest loves to ask me, "Daddy, can I hold you knife?" He will either clutch it like it's his most prized posession, or he will clip it in his pocket like daddy does. It sure keeps him quiet in church!
My oldest has gotten attached to my REKAT Hobbit Fang or my Simonich Cetan. She told me that she had a dream last night that there were some bad guys coming through the corn (field) and I gave her my Fang. When they jumped the fence to get her she stabbed them. Gosh I was pround! (hehehehehe)
My middle girl doesn't care what she gets as long as she isn't left out. I usually clip my CS Mini-Tanto onto her waist.
As far as my guns, I use a little more caution. My handguns are kept out of immediate reach, but readily available. My longuns are easily accessable, but no loaded chambers. All they have to do if they want to see a gun or knife is ask. I never tell them no and I never make them wait. They get to see it when they want, but they must ask. And I taught them gun safety before they ever go to touch one. My oldest had just turned 5 when I asked her one day "What would you do it you found a gun?" I expected to get the "Don't touch, leave the area, get an adult" answer, but recieved, "Pshhh, I'd unload it so sissy and bubby won't get hurt if THEY touch it." Yes, I was beaming with pride. I still am!
"It's gotten to the point that I will ask them, "Do y'all want to see daddy's new gun?" and the aswer will be wrinkled noses, rolling eyes, and a bored sounding, "Nooooo sir."
The only problem that has ever occured was with a nephew. He picked up a pistol frame off the living room floor that his dad and I were cleaning. My in-laws used to hide everything from their kids and didn't teach them any gun safety. Things have changed for the better!