New & Reviewed

CircuitMess STEM Kits

DIYODE Magazine

Issue 69, April 2023

Modern coding learning partners with a traditional electronics learning kit concept in this release from a Croatian startup - by Daniel Koch

We recently received a sample of products from CircuitMess. This innovative company is a recent start-up based in Croatia, and unusually, the kits are all made there, not in China! CircuitMess's own team pick the parts, manufacture acrylic cases and cut parts, and pack the kits themselves. In addition, they are posted from CircuitMess, not a third-party warehousing or distribution company.

The premise of this product is a subscription-based learning journey. There are currently two age-bracketed products on offer, although that is a guide, of course. The younger range ships monthly, while the more complex older range ships every three months, and you can cancel at any time. Most of the kits carry personified names, like 'Synthia' for a synthesiser, 'Wheelson' for a wheeled robot, and so on.

Each kit has a set of skills and knowledge to teach, both in hardware terms and software. Coding is a feature of all of the STEM kits for the older range, but the younger range is really a basic soldering skills and hardware course. The coding is handled through an interface developed and maintained by CircuitMess, for CircuitMess. This means it fits the products well, and if the coding environment can do it, the kit can do it, and vice versa. That's a big part of what makes the CircuitMess kits unique and it's part of what adds to the subscription, too: You're not just buying some parts and a paper instruction book.

We'll have a look at more of the subscription details later, but for now, let's have a look at a few kits! We're also looking at the toolkit that comes with subscriptions of one year or more, but we could not find out if it's available for purchase on its own.


Synthia is a music synthesiser that you can build at home and program with your own device. There are lots of SMD components already soldered to the PCB, so all you have to do is the easier-to-handle through-hole switches, slider potentiometers, speaker connector, and all the case hardware. Once you've built it, the online course runs you through some electronics knowledge like MEMS microphones, and software stuff like digital sampling, through to coding like how to make the onboard LED array do things to reflect the sound. There's plenty more in the documentation, too, much of which is digital and accessed through your subscription log-in.


Chatter is a pair of encrypted wireless communicators. Yes, baby DIY phones! They only deal with written information though, via the keypad. Remember the old mobile phones where you had to kit the number key three times to get the third letter along it? That's Chatter. Except, it has emojis, a colour LCD, and other modes of operation. Because you code it, you can change how it works. It's LoRa based, so it has a far-better-than-WiFi range, too. You'll learn about ciphers and encryption keys, a bit of the history of wireless, and a lot about communication protocols.


The toolkit is a bonus for subscriptions of one year or more. It comes with all the basics you need to build any of the kits, and continue your journey into electronics. It contains a soldering iron, tip cleaning sponge, stand, and a small roll of solder; a spring-plunger desoldering tool; flush-cut side cutters, small long-nose pliers, screwdriver, and an instruction book with basic rules for using each tool safely and effectively to get the most out of it, along with some general construction tips and tricks. Notably, the soldering iron is even temperature-adjustable!

The kit we have has a US soldering iron in it, but that's because we organised our review samples via email and there was a miscommunication. When bought through the subscription service, your country is part of the order and CircuitMess will pack the iron for your country, no matter what plug and voltage is needed. And, if you get one of the two we have to give away, we'll swap out a similar soldering iron with an Australian plug from one of our partner suppliers (unless the winner is in the US, of course!).


The younger range of kits is aimed at basic concepts and soldering skills. We received five examples. Mr Bee uses an offset motor to create vibrations to make the robot move. Marv uses either a momentary or latching switch to light the LED eyes. Capacitron uses capacitors to store a charge, and illuminate the LED eyes after the power is turned off. Bob has colour-changing LEDs and is one of the most basic, teaching about parallel circuits, while Resistron has a variable resistor to control the brightness of the LED eyes.

The PCBs are screen printed with plenty of extra details and are cut into an interesting shape depending on the robot. All are powered by a 3V Lithium CR2032 coin cell, but are intended for ages well beyond the point where these are a swallowing hazard! That said, they're sent directly and do not feature the recent Australian legislated changes to make coin cells difficult to access for younger children. Be careful if ordering them for an older sibling while there is still a risk-aged child in the house, because the coin cell is either loose in the box or in a regular blister pack.


At the time of writing, subscriptions for the younger kits, the Wacky Robots, are $34.99 USD per box, sent monthly and including postage to anywhere in the world. Three-month, six-month, and yearly subscriptions attract discounts, and the six-month and yearly subscriptions also come with a free tool kit. The older kits, the STEM Boxes, are $99.99 USD per box, sent every three months. One-year and two-year subscriptions attract discounts, and come with a free tool kit. You can cancel the subscription at any time, but it does auto-renew so if you do change your mind, you have to opt out. That's like pretty much any other subscription service we can find, including all the streaming services.


The kits are well thought out and well put together. The web documentation is healthy and expands more than a paper book ever could, and is also more engaging. For the STEM kits, the web interface and coding is comprehensive but very accessible and not overly complicated. The kits might be expensive, but the poor exchange rate right now is part of that. It's hard to compare value for money because there is really nothing else quite like it that we have found. It will really be up to the individual to decide if they're worth it, but we can certainly attest to the design and build quality and of both the kits and the supporting material.

Where to buy?

Don't want a subscription? If a subscription doesn't suit you but you want to you get your hands on one of the CircuitMess products, our friends at Pakronics sell them individually.

UPDATE: Sept 2023

Recently, CircuitMess has started to give more importance to their blog ( and they have many new topics planned for the near future.

Their blog makes small, yet impactful, changes in today's kids' learning, creativity and way of thinking for the better. Some of the topics include:

15 Cool Science Projects Your Kids Can Do at Home
7 Strategies to Reduce Your Kid’s Screen Time
10 Best DIY Subscription Boxes For Kids That Will Spark Curiosity
How to Teach Your Kid Problem-Solving Skills Through Games and Activities