Jack and Jill Fetching A Pail of Water
Two bowls or buckets, a big sponge and water.
Take either two bowls or buckets and a big sponge. Fill the first bucket with some water, but not all the way full. Have your child soak up the water with the sponge and then wring it out in the empty bucket. See how many times or how long it takes for them to empty the first bucket and fill the second using only the sponge.