How to make your own add-on boards with household materials

How to make your own add-on boards with household materials

Tanya Fish
Tanya Fish

You may think that if you’re starting out running a code club, you need a huge budget to buy a load of materials - the truth is, the hardware is, well, hardwearing and almost guaranteed to work, but sometimes a quick-and-easy homemade solution can work as a stopgap. I’d like to share some boards I have successfully made with Year 5’s in my code club, and examples of what you can do with them. I have assumed you have micro:bits and crocodile clips.

Traffic Lights

You can make a set of traffic lights for use with your micro:bit using the following materials:

  • Piece of cardboard
  • Silver foil
  • Glue stick
  • 3 x LEDs (red, orange, green)
  • Sellotape

Step 1:

First, cut a piece of card about the size of a playing card.

Cut a strip of tinfoil the length of the card.

Bend the legs outwards on the LEDs and give them a bit of a bend.

Card, foil and LEDs prepared for the next step

Step 2:

Glue the left third of the card as in the diagram, and smooth the foil down on it. Bend the foil around the back of the card and glue that down too.

Take some more of foil and glue three patches around the right-hand third of the card. Make sure they don’t touch. Make sure they go round the back too.

Front and back of the card with foil glued on

Step 3:

Now we’re going to attach the LEDs. It is very important that the flat side of the LED (negative) is on the strip side, and the rounded side (positive) is on the patch side. Tape the LEDs down with one leg on the long strip of foil, and the other leg on a single patch, as shown in the diagram.

Tape down the LEDs, taking care to put them the right way around.

Step 4:

Finally, wire up to your micro:bit as in the diagram:

Use crocodile clips to attach your board to the micro:bit.


I used the following code to cycle through the pattern a real set of lights does. You might want to change the timings, or try to make different light patterns like running lights or a Knight Rider style Larson scanner.

The red light is connected to pin 0, the yellow to pin 1, and the green to pin 2. Connect the ground strip with one crocodile clip.