The Micro:bit timer is perfect for games like Charades and pictionery, or is a competitive addition to ones like Connect 4. The timer can be coded to whatever time you want, and when the end of time is coming up, each LED will gradually disappear and all will be out when your time is up. Follow the link below for the Micro:bit coding. Happy playing! 

You will need:

1 x 3D printer + Filament

1 x BBC Micro:bit

2 x wires with crocodile clips 

1 x AAA battery pack

2 x AAA batteries

Micro:bit coding: https://www.microbit.co.uk/tlfcxl