Easy Circuit Experiments – Rainbow Salt Circuit

This salt circuit is one of our favourite projects we’ve done in a while. It’s easy circuit experiments that sometimes provide the most fun for kids because they can do them over and over again. With the STEAM addition of arts to this project, it also means a different beautiful circuit each time!

Easy Circuit Experiments – Rainbow Salt Circuit

Rainbow salt circuits are an easy circuit experiment that all ages will love

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We love building circuits from circuit bugs to circuit flowers, potato circuits to squishy circuits. There is something so satisfying about a project that results in power and light!

Yesterday my friend, Ana over at Babble Dabble Do, released her book STEAM Play & Learn and it immediately raced to the top of the bestseller lists! I am honestly not surprised at all. I was lucky enough to get my copy already and it is absolutely brilliant! She has written the book to appeal to kids, so they get really excited about learning. No need for an adult to guide learning, just let them at it.

In fact my kids were so excited by the book they started begging me to do some of the projects. First on their list was creating a salt circuit.

Now we are circuit builders it is something we love to do, so I started digging through our tinker bins grabbing everything we needed.


STEAM Play & Learn – Check!
Salt – Check!
Glue – Check!
Paperclips – Check!
Food Colouring – Check!
Paper – Check!
LED – Check!
Battery Pack with 2 Double AA’s – Oh oh!


I am really not sure why I don’t have a 2 x AA battery pack. Like seriously, circuits are what we love to do! But we have never done one that called for one of those packs.

Now I could have run to the store and bought one. But this is circuit building and to become proficient with circuits we need to learn how electricity flows and how to build circuits that work with the supplies we have.

In other words, I wanted my kids to MacGyver the heck out of this!


So my first challenge for the kids was to build a circuit that would light up the LED light bulb. Before we started we tested the LED on a button battery to make sure it worked. I didn’t want them going through all of this only to discover the light bulb was burnt out!

Then I gave them a pile of alligator clamp wires, AA batteries and some single battery packs.

It didn’t take them long to figure out how to daisy chain the battery packs together to increase the voltage so it would power the LED. STEM learning for the win!

Building a circuit from our tinker kit


Once we had our power source sorted out, it was super easy to follow Ana’s instructions.

After folding two sheets of paper in half, we added our paperclips. Then the kids got to draw their designs with glue. Make sure it is a good thick line of glue.

Then we added salt. And some more salt. It needed a lot of salt. At first our circuit didn’t work, so we had to add even more salt!

Then we added our food colouring to make a beautiful, colourful circuit pattern. Although I have to say, hers is WAY more pretty than ours! We used regular liquid food colouring and it just didn’t travel and blend as nicely. Next time I might try water colours. The kids didn’t care though, they still thought it was awesome!

Then it was the big moment, placing our LED and watching it…. not light up.


Like any great experiment, we had a failure on our hands and needed to do some scientific investigation to figure out what was going on. We referenced the book where Ana mentioned we needed to use a lot of salt. So first step, we added MORE salt.

And we had a flicker of light!

Now we had to look at our connections. After some playing we discovered it was important to ensure the entire leg of LED needed to be well submersed in the glue.

We did it! We built a functioning Salt Circuit!

An easy circuit experiment for all ages, salt circuits are fun for all ages

Onto the Next Activity in STEAM Play & Learn

The kids had so much fun with this activity, they can’t wait to do more. Ana included lots of ideas for how to take the lessons from this activity and apply them in other ways, plus a great explanation of the science behind how salt circuits work. And I know the kids are going to want to try some of those ideas too. But the gorgeous pictures have them browsing and from their excited chatting, I think the Newton’s Cradle engineering project is next on our list. But who knows! The boys are loving all the gorgeous pictures and projects that are inspiring so many ideas. If you are looking for a fantastic book to inspire your kids, make sure you check out STEAM Play & Learn!

Building salt circuits is an easy circuit experiment that appeals to all ages. Turn it into a STEAM project with the addition of some beautiful colours and designs.