For the safety conscious among us, I've been drilling into my daughter that she never touches the soldering iron (ever!) since I don't trust her distracted 3yr old head to recognize when the light is on.
At no point in these pictures was the iron on, but she is forever asking to "see my work" and I've shown here just about everything else. Every time she asks me about all the parts and then Make Magazine decided it was "Teach Your Family to Solder" Makecation week so I decided to teach her how to solder, without actually applying heat.
1/2 the time was drilling her with "when do we touch the soldering iron?" to which she successfully responded several times "only when Daddy says so!" and so forth. She's very clear that touching it without my full and complete attention and permission is extremely dangerous.