Step 1: Make it
What is it?
Make a reaction game with real physical switches you can bash as hard as you like!

How it works
- Make two physical input switches using cardboard and tin foil – similar to the ones used in the Pressure switch alarm project.
- Connect them to the micro:bit pins as in the picture – one tin foil pad on each switch goes to the micro:bit’s GND pin, and the other is connected to pin 1 or pin 2 depending on whether you are player A or player B.
- The program waits a random time between 1 and 5 seconds, then shows a heart on the LED display output.
- You can’t hit your button before it lights because it uses Boolean logic to stop anyone cheating! Boolean variables can only have two values: True or False. The game started variable prevents either player pressing their button too soon by only checking which button is pressed while the game has started.
- An infinite loop keeps the game running so you can keep playing.
What you need
- 1 micro:bit
- 4 crocodile clip leads
- Some scrap cardboard, tin foil, glue and scissors
Step 2: Code it
Step 3: Improve it
- Use variables to keep track of each player’s score
- Add a timer to show how quick each winner’s reaction was
- Track which player has the fastest reaction time
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