So.. My sister is an elementary teacher. She saw an amplifier I just finished, and asked if I could make a simlpe ciruict to show to her kids, and explain the basics of how it works. I was looking for something like a LED caculator. Maybe something that could add by push buttons then shown on LEDs. Maybe just reset by a switch or something. I checked
this post about a 7-segment LED Counter, and thought something more interactive would be better. If anyone had any other ideas that would be simple, and somewhat easy to understand that would be great.