You can (and we do) teach the science as well as the story.  In addition to having a Chemistry professor and a science teacher in the congregation, we have had a number of science-focussed kids over the years.  They want to understand the "why", not just the story connection, and actually learn more about the story after the science is explained.  It is amazing how often the science details can be tied into the story connections.  Talking about polymers and surface tension is just another way of exploring God's creation and doesn't take away from the object lessons that are the main focus.