If it has a screw on it, my three year old will use any screwdriver he can reach to unscrew it. If there's a nail, he will use his pretend hammer or anything he deems fit to use as a hammer to hammer it in. If it's broke, he touched it. If it's fixed, he hasn't yet touched it.
This kid is not allowed in my office for the reasons set forth above, but every time I venture out of the home to leave him with Dad, my office usually gets touched. My printer was broken a couple of times. My desk drawn all over, that means my blogging notepad that I use to keep track of the editorial calendar at Happily Blended, totally drawn over. Thankfully it was highlighter.
One time he made it into my office and colored my flat panel computer monitor. He's lucky highlighter washed right off!
So ... all I have to ask is this; are boys born with the gene to just want to tear everything apart so they can find a way to fix it?