When I was in Elementary school (back when dinosaurs roamed the earth), Bell Telephone had a wonderful series of free "Adventures in Science Kits" that helped me get my start in electronics. Look at this manual from one of the kits: http://wedophones.com/TheBellSystem/pdf/kit2.pdf
Beginning on page 45 it explains how to make your own solar cell using materials provided in the kit. Take a look at page 46, where the instructions include steps such as "Diffuse the boron into the silicon by high-temperature heating" and "Deposit nickel on the unmasked surfaces by electroless plating". I think it is unlikely that you would find instructions like these in kits intended for Elementary school students today.
@JeffL_2: When I see articles with titles like "what the C language is actually useful for" I have to shake my head in amazement, I could see that happening maybe in 2113 but not in 2013!
Of course, that title may have been selected to make someone like you shake your head and then open it up to see just how silly it is... at which point the author of the article just got one point (LOL).
@bbaudis021: This gets really scary as one considers the compilers' bugs...
You are right, it does get scary!!!
Take something like floating-point that software developers use in their programs all the time ... without any clue as to how it actually gets performed inside the computer and where any errors might come from...
@Duane: My kids can't even write in cursive. They happen to have some basic survival skills like map & compass & such from scouting, but many people I know likely couldn't survive more than a night or two in the wilderness.
I'm not sure that I care about cursive ... but I do worry that my 18-year old son has no idea how to read a map -- he relays on GPS directions -- goodness knows I've tried to teach him, but he has zero interest (sad face)
@Duane: I've run across an article or two lately about hobbyists building their own vacuum tubes. I also recall reading about someone home etching primitive ICs...
I love the idea of building something with hand-constructed vacuum tubes.
I once saw someone make a transistor by hand in a small furnace -- very interesting.
I have thought about making my own relays and then building a digital computer out of them ... but then I think of all the time it would take ... plus I also like the idea of using antique relays of th etype I talked about in my Mock Relays column
Blog Doing Math in FPGAs Tom Burke 23 comments For a recent project, I explored doing "real" (that is, non-integer) math on a Spartan 3 FPGA. FPGAs, by their nature, do integer math. That is, there's no floating-point ...