Good video for education about water cycle
NASA: The Water Cycle: no speech (1.22)

Tip how to to demonstrate water consumption with children:
Thrifty and wasteful hand washers
Accessories: buckets, 1 l measure, dynot, etc. containers at the bottom of the pool, two water points preferably close together

Divide the outfit into two equal groups:
Thrifty hand washes: Turn off the faucet whenever soaping, striving to be accurate and effective.
Wasteful Hand Washers: Gossiping, chatting and concentrating on everything else during hand washing

The difference in water consumption is compared and measured.