I use to teach electric shop courses. This "learning toy" kit looks like it is so much fun and the best way to get kids thinking about technology, see what's under the hood and make inventions.
click here
If you buy put TWIT in the promo code.
I guess it's pricey but so were Erector Sets [the big set in the big metal box] also expensive. I only had the one in the cardboard tube with the screw on lid but I loved it.