One of my children's favorite piano activities is "storytime." They especially love it when they are the star of the story. I encourage them to "make sounds" at the piano to go along with story. For example:
One day Dan and his dad were going four wheeling in the mountains.
First they climbed up a steep mountain very slowly so they could look for deer (Play white keys on the piano going up one key at a time slowly).
Then they decided to stop for a while by the lake so they could eat some fruit snacks and look at the fish in the water (Stop on a white key and play it repeatedly).
All of the sudden they heard a funny bird in the tree (Play high keys imitating a bird)
This helps reinforce concepts of high and low sounds and helps children play more artistically in the future as they learn to create sounds that represent emotions and objects in the world. Its also a great way to encourage them to compose from the beginning.