My first in-class circuit was a simple LED-3V battery combination. Using copper tape to fasten the ends of the LED to the negative and positive sides of the battery, I fashioned a rudimentary flashlight. I used a rolled-up tube of art paper, tape to hold the tube together, and the LED-battery combination, taped into the inner lining of the tube.
My second circuit was an attempt to make a series circuit with the 3V, copper tape, and 3 LEDs. I knew that to wire the series together, the positive end of the LED had to be attached to the negative end of another LED, and so on. It didn’t work, and it was only after speaking with the instructor after class that I learned from her that series circuits don’t work if made from 3V batteries. The more you know!