On 10/22/07, Mark Tapley <mtapley at swri.edu> wrote: Yes. I had the Radio-Shack-badged one. That was the first one I had - the overlays inside were, IIRC, printed tissue paper. Yep. And the whole thing arrived as bagged fiddly-bits - I remember taking more than an hour to assemble. I remember the contacts weren't great on the best of days. I think my step-mother threw mine out when she decided my room was too messy. :-( My step-brother had the later Radio-Shack model - the lights were down inside the body of the unit, with flat, plastic printed overlay strips that mounted flush to the face of the unit, and rather than small holes with brass contacts inside the switches, it had external springs like the 150-in-one project kits of the day. It was also sold pre-assembled, IIRC. I did most of the projects in mine, but the one I remember best was the goat/cabbage/fox puzzle. There were graphics on the 3 left-most and 3 right-most bulb spots for the puzzle elements, and a light to signify that you had an error condition (i.e. - the fox ate the goat or the goat ate the cabbage). You flipped the switches to migrate the elements back and forth across the "water", and you might have pressed the button to see what "got et" on that pass, if anything. My only real complaint with it as a teaching tool was that even though I did all the projects, there was no abstraction of the underlying concepts presented. I knew what logic gates were, but at that age, wasn't able to extrapolate on my own how multi-pole switches related to logic gates. I don't recall there being any schematics printed for the projects, either; something that might have helped illustrate what was going on under the hood. It was fun to play with, but I don't think I learned that much from it, unfortunately. I think the N-in-one electronic kits were better as teaching toys. -ethan