The Micro:bit night light is perfect for children who do not like the dark. You can edit the coding to produce light levels as bright or as dim as you like, and simply press A/A+B button if you change your mind.
The 3D printable case is nicely decorated with aspects of night and day, and the Micro:bit fits in securely. If you wish, decorate the case and make it your own. You could paint the sun, moon and stars!
The battery holder can take any size up to 2 x AAA batteries. If you have a battery case with an on/off switch, you could add an extra light mode as you wouldn't need B button to turn it off. Use the code below.
Block Editor: https://www.microbit.co.uk/vulnri
I have used 20% infill due to the thin parts.
You will need:
1 x 3D printer Filament
1 x BBC Micro:bit
1 x JST connector to battery pack
Superglue - Seek adult help if you're under 16!