Aug 21, 2014
Summer Special: Squishy Circuits
Today's project: Squishy Circuits
conductive dough (a cooked dough with: water, flour, salt, cream of tartar, vegetable oil, food coloring)
insulating dough (a no-cook dough with: distilled water, flour, sugar, vegetable oil)
LED lights (similar to this) (you might also try out vibration motors)
waxed paper (optional, makes clean-up slightly easier and helps define workspace)
What we did:
First, I explained the two forbidden experiments:
1. Touching the battery pack leads to each other (it will burn out the batteries)
2. Touching the battery pack leads directly to the LED's (it will burn out the LED's)
Then let them know that pretty much anything else was fair game.
Next, I gave a quick, mini-lesson in electrical currents. My explanation involved this drawing (the green breaks between the purple represent the insulating dough) and quite a bit of happy little electron humming as they zoom along the path, heading back home to the battery pack and then their groaning with effort as they encounter the insulating dough and are forced to jump over the LED bridge and light up that pesky light along the way before they can return back home. It was oh-so-technical. My apologies to scientists and electricians everywhere.
Finally, I encouraged everyone to try out one or both of the layouts I'd illustrated, but to then get creative and design their own squishy circuits shapes. Here's what they did:
What if we just skip the insulating dough and use gaps instead?
Apparently, this is a Pokemon symbol?
-If you want to do this project more than once, you should know that the insulating dough only lasts a few days in the refrigerator (and even less if left unrefrigerated). The conducting dough can last at least a few weeks in the fridge.
-If dough gets too mixed together, just toss it at the end of the event. The more mixed it is, the less it retains its insulating or conducting properties.