We used a micro:bit V2 with a Crazy Circuits Bit Board and some LEDs to build a simple reaction game as a paper circuit project. The micro:bit V2 has a built-in speaker which we utilized for sound effects, along with the built-in LED matrix to show the score. The sticky Maker Tape handles all of our connections and allows current to flow to the LEDs and allows us to easily make a paper switch!

Maker Tape is a conductive nylon tape. Unlike copper foil tape it is very strong (you can't "rip" it, but can easily cut it with scissors) and it is conductive on the top and bottom, and all the way through, so you can easily overlap it. For this project the 1/8" wide tape works well for connecting to the Bit Board, but if you have 1/4" wide tape it can make things a bit easier for connecting the LEDs and constructing your own paper switch.

Note: For some in-depth explanation of the code and a template download the PDF file.

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Reaction Game (Paper Version).pdf
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Supplies

Brown Dog Gadgets does in fact sell kits and supplies, but you don't need to buy anything from us to make this project. Though if you do it does help support us in creating new projects and teacher resources.

Electronics:

Crazy Circuits Bit Board
micro:bit V2
Maker Tape (1/8" Wide)
Maker Tape (1/4" Wide) - (Optional. You can do this project with 1/8" wide tape if desired.)
4 x Jumbo 10mm Diffused LEDs

Other Supplies:

Paper or Cardboard

Tools:

Computer (with Internet access)
Scissors

Step 1: Let’s Make a Game!

We’re going to use a micro:bit along with a Bit Board and some LEDs to make a fun game that will test your reaction time.
Game design involves thinking about the game objective, rules, parameters, mechanics, and playability. We started with this slide exploring how our game would work.
A series of LEDs will light up in sequence, and when the fourth LED is lit you need to press the button. If you time it right you’ll get a point!
When you get 25 points you’ll win the game!
But wait! Each time you press the button successfully the game will speed up… and if you press the button at the wrong time you’re score will go down.
We’ve written all the code, and our attached PDF will show you what to change to affect the gameplay. You can make it easier or much more difficult!

Step 2: Build Your Circuit

We're going to build our circuit on paper (or cardboard.) We'll use Maker Tape, along with standard LEDs and we'll fashion our own button using Maker Tape and some paper.
The great thing about Maker Tape is that it is conductive on both sides and all the way through, so if you need to overlap pieces of it, they’ll still make the needed connections just fine.
Feel free to adjust the layout if desired. Maybe you want more space between your LEDs, or want the button placed somewhere else… As long as everything connects to the correct pins it should work fine

Hey! Those LEDs don't have resistors connected to them! We're using our own Jumbo 10mm LEDs which have built-in resistors made specifically for our paper circuits projects, so even though you don't see a resistor, it's there!
There's a PDF with more on the circuit and the code.

Step 3: Sticking Maker Tape

The Bit Board, like all of the Crazy Circuits components, are meant to be used on a LEGO baseplate. Typically the Maker Tape will be attached to the studs on the plate, and then the Crazy Circuits component fits on top, making a good connection.
For this project we'll use a different method of connecting things. But first, let's look at the options...
While it's possible to just stick Maker Tape onto the connection rings on the Bit Board, it doesn't always create a good connection, especially with the 1/8" tape.
So let's explore another connection method...

Step 4: Looping Maker Tape

We're going to thread the 1/8" Maker Tape through the holes in the Bit Board, and then fold it over on itself.
You can use a short piece for this, since we'll want to do this to all of our connection points. Once they all have these little "tape tails" we can connect them with Maker Tape to the LEDs and the switch.
Make sure your loop is tight! A tight connection makes a good electrical connection!

Hey! Could I use alligator clips for this project? Sure! We really prefer Maker Tape, but you can use alligator clips to connect things to the Bit Board, as long as you are careful and do not allow them to inadvertently short anything out and cause damage.

Step 5: Attaching LEDs

Let's talk about connecting LED legs with Maker Tape. If you've built any of our paper circuits, you'll notice we usually use 1/4" Maker Tape instead of 1/8" Maker Tape. Both will work, but the wider tape works much better when connecting LEDs into paper circuits...
That said, you can use 1/8" Maker Tape, but you'll want to get a good connection.
Here's a few tips!
You may find that connecting the tape parallel rather than perpendicular to the leg will create more surface area for the connection.

Step 6: Attaching LEDs (The "Sandwich")

Here's another good trick. You can stick down a piece of Maker Tape, then put the LED leg on top of that, and add another piece of Maker Tape on top to hold it down.
This creates a "tape sandwich" and ensures that the LED leg is touching conductive tape on the top and bottom. Again, making a good connection is the goal.
If you find that an LED isn't lighting up when it should, check your connections! Press down on the tape to secure things, and if needed, add a bit more tape.

Step 7: Attaching LEDs (Wider and Overlaps)

For this project, or any paper-based project, the 1/4" Maker Tape works better for sticking down LED legs and for making paper switches.

If you've only got 1/8" Maker Tape, you can always overlap it to make it wider, since it conducts on the top and bottom and all the way through.

Step 8: Make a Switch

The included PDF file has a short guide on making a simple lever button for this circuit, but you can explore other options and test a variety of switches.

Step 9: Load the Code

We'll be using makecode.microbit.org to program our board. It uses a simple drag and drop block interface.
We're going to load the following code for our Reaction Game program: https://makecode.microbit.org/_6CqWTjct2gjC
The included PDF for this guide goes into great details explaining the code and what each section does.

Step 10: Test It Out!

Ready to play? Let’s do it!
Once you’ve got the code loaded the game should start right away.
Get ready to press the button when the fourth LED lights up.
Press it at the right time and you get a point! Press it at the wrong time and you lose a point!
Every time you get a point the game will speed up.
When you win you’ll hear a victory sound and the game will restart so you can try again.
If you want to start over or let someone else play, just press the B button on the micro:bit to start a new game.

Step 11: Take It Further

In the PDF file we’ve highlighted what parts of the code can be changed to adjust the gameplay.
You can change the desired score, the initial speed of the game, and how much faster it speeds up after each correct press.
For this game we set the defaults to what we considered to be challenging but not too difficult, you should feel free to adjust things and see what happens!