-> We used breadboards, with logic chips, and LEDS. 
->  Hooked up OR, AND,
-> NOR, etc chips in various ways, According to your equation, your
-> lights would light up differently.  Seriously, I didn't get truth
-> tables, etc. until I'd lit up a bunch of the little red lights.
 SK> I've not heard of "breadboards" before. Where could 
 SK> I locate such items?
 SK> Are you using these this year in your class?
Ok, another item to dig up--I know there is a source for these also, lots of 
fun to use with partners or groups. Radio Shack has some electronic 
experiment boards - although not breadboards, they can be used as such. Lots 
of fun. If you don't get the info here, I will dig through my Lesley College 
material as they use a breadboard kit in one of their classes. 
--- Maximus 2.02
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