This activity can be adjusted to any age, any topic & any ability level. Individual, pairs or teams. I've used with Yr 7 to Extension 2.
You will need to buy a lockable box & a 4 digit combination lock - I got mine at Bunnings.
24 January 2021 Edit: 24 January 2021
Shared by Hans
Attribution: Thank you Chris Smith, a TES wizard, who happily shared this idea.