Why Ducks Don't Get Wet

This morning we conducted an experiment to prove why ducks don't get wet. We discovered through our observations and predictions made that ducks must preen their feathers throughout the day to keep their feathers covered in oil. While we were making observations we noticed how the water rolled right off the oily feathers! Then we came to the conclusion that that is why ducks don't get wet!
This is a great book series if you are looking for science books. I always find a great experiment to do at the end of the story!