LEDs + Dough = Squishy Circuits!
I have been searching for good engineering projects for the elementary ages that I can add to my Makerspace classes. I came across Squishy Circuits article in Make Magazine. Just a few materials and kids can learn about simple circuits, which is the perfect fit for a Makerspace class!
Before I jump in and design a class around them, I decided to try them out with my niece and nephew during their recent visit.
Squishy Circuits only need a few items
Power Source (I used a 9V)
alligator clips
5mm LED lights with the bare prongs http://amzn.to/2mxr5z1
conductive dough (recipe below) or Play-Doh
insulating dough (recipe below) or Modeling Clay
tools for shaping your creations (rolling pins, clay tools, etc)
You can either make your own (my preference) or use Play-Doh and modeling clay. I found the dough recipes from Make Magazine. I like making it because I can make a greater volume of dough for cheaper than the pile of Play-Doh I would need to buy! Plus, all the colors I can make. I have been instructed I need to make blue dough.
Conductive Dough
1 1/2 cup flour
1 cup water
1/4 cup salt
9 Tbs of lemon juice or 3 Tbs cream of tarter
3 Tbs vegetable oil
food coloring
Reserve 1/2 cup of flour. Combine all of the remaining ingredients in a sauce pan and stir until the mixture forms a ball. Place dough on a floured surface and allow to cool slightly. Knead in approximately 1/2 cup of flour to make the dough a soft consistency. Store in an air tight container for up to 1 week.
Insulating Dough
1 1/2 cup flour
1/2 cup deionized/ distilled water
1/2 cup sugar
3 Tbs vegetable oil
Reserve 1/2 cup of flour. Mix all remaining ingredients together in a bowl. Knead in enough of the 1/2 cup of the additional flour to make a soft dough. Store in an airtight container for up to one week.
Some helpful hints if you are unfamiliar with circuits and these LEDs:
Insert an LED so its anode (long lead) is in the positive battery lump, and its cathode (short lead) is in the negative battery lump. Attach the alligator clip from the negative side of the 9V to the same section of dough that the cathode(short lead), the alligator clip lead from the positive battery terminal to the side of the dough that contains the anode (long lead).
Always attach LEDs or other components to the dough. Never attach them directly to the battery pack. Attaching the LEDs directly to the battery can damage the LEDs from too much current.