I work at a library in a low-income, high-needs community with a lot of new immigrants. So when we decided we wanted to run a Squishy Circuits maker session, I had to adapt the program to our library's environment. Many of the kids in our neighbourhood are not familiar with electronics and technology. Hence I needed to keep our Squishy Circuits program simple and be sure I gave them a little bit of preamble on the basics of circuitry, and show them a couple of examples of squishy circuits I made in advance. Though many people involved in maker culture will tell you this goes against the investigative spirit of maker culture and its focus on learning through doing and learning from failure, I can tell you that if I didn't do this the kids wouldn't have had the slightest idea what to do and therefore had no starting point from which to start experimenting - they would just leave in frustration. It has happened before. Through trial and error I found that once I do this preamble, they get it and are fully willing and able to experiment and explore on their own. They might need a little more coaching and/or reminding here and there of the science or concept behind what we are doing, but by the end they usually all get it.
This tutorial covers the teaching method I used in order to communicate to the kids the concepts necessary to understanding how to make use of the dough and electronics. It also goes over how to find and assemble the electronic components if it's not something you are familiar with (how to know which battery packs to get, what voltage should the LEDs and motors require, how to solder, etc.). Unfortunately the Squishy Circuits website doesn't cover this. But believe me, the materials are all readily available and no great knowledge of electricity and electronics is required.
Step 1: Materials
For making the dough:
- Plain white all-purpose flour
- Small container of vegetable oil
- Large package of salt
- Cream of tartar or lemon juice
- Food colouring
- Access to a stove/hot plate and pot
- Distilled water
- LED bulbs with two leads
- Toy motors
- Battery packs with leads
- Soldering iron
- Needle-nose pliers and/or wire crimper/stripper
The battery packs, toy motors, LED lights, and wire crimper/stripper I bought at an electronics hobby store because I found them there at the best price (budgets are always a concern for schools and libraries!) however if you take apart many common-place toys and gadgets, you'll find these items inside.
A soldering iron and solder can also be bought at an hobby/electronics store or at hardware store. A cheap soldering iron will do the job just fine, and any solder is good as long as it is not a super thick gauge and it is not acid flux. No clean is ideal, and lead-free is not, but these are not hard-and-fast rules.
I promise that soldering is not that difficult. In fact, it's a lot of fun. Here is a great tutorial. There are also lots of tutorials on Instructables.
Step 2: Getting the Electronic Components Ready
This you will want to do in advance.
If you find you have bare wire ends (which is most often the case) like this then you will need to solder terminals on (see blue arrows in the photos for wire ends that need terminals). Terminals can be bought very cheaply at hobby and electronics stores, or online. I used fork shaped ones but really, you could use spade or circle shapes too. It doesn't matter. I like the ones with an end that is meant to be crimped to the wire with needle nose pliers or a wire crimper (see photo). It just makes the soldering part easier because the terminal will be kept somewhat in place. Heck, if you are really good and the terminal holds on its own after crimping, you might not even need to solder. But, if you have super steady hands, or second set of hands to help you, then go ahead and try the flat end ones! Just don't buy terminals with a plastic end. You will have nothing to solder to!
A quick note: if you find you have some sort of specific end to a battery pack, resulting in no wire ends (like the one in the photo) you can still use it. You will just need a wire stripper/crimper to cut the end off and strip back some of the black and red coating to reveal the wire in order to be able to solder it to a terminal.
For the battery pack, you can use almost anything. 4 x AA is ideal, but we were able to get 2 x AAA to work, though the battery wires had to be placed very close to the motor or LED light within the dough in order to work. Also, the lower the volt requirement for the LEDs and motors, the easier they will be to make run.
Step 3: Make the Dough
I make the dough in advance too. The directions on the Squishy Circuits site are very easy to follow.
Step 4: Teaching Circuitry Basics
Give a little preamble about the basics of what makes a circuit work. I just printed out the “Circuit Basics” slides from the Squishy Circuits website and blew them up a bit so the kids could see them easily. I then went over the slides with the kids, and also mentioned that a motor could be used instead of an LED. I made a quick example as I was talking of a closed circuit vs. open circuit vs. short circuit in order to illustrate.
I also give a little talk about safety concerns, which mainly is just that you should never connect the terminals directly to the battery pack, which may cause the battery pack to overheat and the LEDs to potentially burn out.
Step 5: Let the Kids Go Nuts!
I mention that they could make sculptures and use the lights to make certain parts light up, and the motor to make other parts move. Also made extra salt and lemon juice/cream of tartar available and suggested that maybe they could make the conductive dough more conductive by adding extra salt and/or lemon juice/cream of tartar and explained how salts and acids relate to conductivity.