A relay game to gives the kids an idea of how tiring it is for people in third world countries to get water.
As many 2 litre bottles, with lids, as appropriate for your group.
Fill the water bottles to an appropriate weight for their age group
Split them into equal teams (Patrols, sixes, lodges)
One half of the Team at one end of the room and the other half at the other.
Relay race to see who can transport their water the fastest ensuring everyone has a go.