* Artificial life
These are not the droids you are looking for.
AFTERNOON
* Basics: electricity, switches, motors
http://music.columbia.edu/~douglas/classes/electronics_workshop
http://en.wikipedia.org/wiki/Switch
http://music.columbia.edu/~douglas/classes/motor_mania
Batteries, wall warts, regulated supplies
Other power options: solar, wind, steam, etc.