When I was a kid, before anything electrical was thrown away, I was given the opportunity to tear it apart with a screw driver: alarm clocks, cassette decks, record players, VCRs and appliances. I realized that my own kids haven't had that kind of experience. Everything is composed of integrated circuits these days. If you tore apart a modern day alarm clock you'd end up with a circuit board and an LCD. Boring. Crack open the iPod your sister ran through the washing machine? A circuit board and a battery. Yawn.
My wife says I can fix anything, which may be an exaggeration, but I'm certainly not afraid to crack it open and see if I can at least diagnose the problem. I realized that my kids may not be so inclined to do so down the road. I realize that there are inherent dangers in messing around inside old electrical objects, from capacitors to lead, but there's also so much to be gained.
These days there are very few moving parts. There are always exceptions, CD and DVD players have a number of mechanisms, as do PCs. But in the 80's it seems that so many other household items had mechanical functions. Cassette players, record players and VCRs (those were always a favorite of mine). Those old flip alarm clocks were a wonder! I don't recall a single device saying, "NO USER SERVICEABLE PARTS INSIDE". They may have, but there was certainly some curiosity actually see how it worked, and I wasn't actually "servicing" them back them, as they were already dead or dying.
I put a lot of credit in Legos as an instructional tool growing up as one of those ways of learning without actually realizing you are learning, but I think tearing apart everything I could get my hands on was a great experience as well. I need to find things for my son to dig his hands in to