Scatter some cones (divots) across the area, some the right way up, and some upside down. Split the group into two teams - 'Hackers and Greenkeepers' - and spread them out across the area.
On the word 'Go' the Hackers run round turning the divots upside down and the Greenkeepers must turn them the right way up.
After a set period of time, count the divots to see how many are the right way up and how many are upside down.
Change the teams round and start again.
Progression:
Easier: Reduce the distance between the divots.
Harder: Increase the distance between the divots.
World Rugby has reportedly conceded Aaron Smith's disallowed try in the World Cup final should have stood.
"It is not only useful for staff who are experienced but a valuable tool for those subject staff who have to take teams."
The variety of sessions across sports - sometimes we steal session ideas from one sport and use them with another.