Step 1: Make it
What is it?
A nightlight that lights up your micro:bit’s LED display in the dark.

How it works
- Like the Sunlight sensor project, this uses the micro:bit’s LEDs as a light sensor input. Cover the display with your hand and see if it lights up.
- It uses selection to sense if the light falling on the micro:bit falls below a certain level – is less than (<) 100. If it is dark, it lights up the micro:bit display, else it clears the screen so the LEDs are dark.
- You may need to adjust the threshold number 100 depending on the lighting conditions where you are.
- What do you think you could use this nightlight for? Could it help improve safety for people or animals in the dark?
What you need
- micro:bit (or MakeCode simulator)
- MakeCode or Python editor
- battery pack (optional)
- a source of light and something to cover the micro:bit with
Step 2: Code it
Step 3: Improve it
- Change the image to show a moon or star when it gets dark.
- Attach the micro:bit to your bag or clothing to use this as an additional safety light when walking or cycling – can you make it flash to stand out more?
- Try this MakeCode project that makes the LED display get lighter and darker depending on the amount of light falling on the micro:bit. Where else have you seen things that react to light in this way?
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