The circuit that we worked on was a 555 Timer based One-Shot (see monostable multivibrator.) The purpose of this circuit is to provide a steady, constant, digital signal that goes high for a predetermined amount of time no matter what the input trigger does and then shuts off until triggered again. In other words, no matter how many times you press the button on the circuit, the output generated will remain high for the set period and go off. Once it is off you can then press the button and it will repeat the same thing again. In the electronics world this is a very important, yet simple circuit. The 555 Timer is used in almost anything that requires a simple clock. Even more important for the purposes of our workshop, the circuit has several soldering points, and involves some creativity with component placement.
If you have any other questions about the circuit, feel free to shoot me an e-mail at [dhess at midsouthmakers dot org] and I can attempt to explain (or confuse you) even more. The links for the circuit diagram and Fritzing file should be below. If you have any issues getting to the files, just leave a comment.