Re: Who taught these children ??
I think it depends on the kind of kid you're showing this stuff to. There will be kids interested in working on older stuff, probably just for the "how did they do this without current tech?" value. Maybe an Apple II isn't that good to spark that question on a kid, but I've seen it happen with mechanical stuff. That is, stuff like a mechanical calculator; that'll garner a lot of interest. "Wow, this thing can add, subtract, multiply and divide without using electricity? No microchips? Cool!!!"
An Apple II probably would garner more attention if you can show at least basic stuff working like "phonebook program" or something like that. I know my dad was able to make me get interested in his age-old TI-59 calculator as a kid.