I don't know how many times I've heard the story, "My child played with the boxes that his/her Christmas/birthday toys came in rather than the toy!" Imagination is a powerful tool and encouraging it is of great importance! Letting children play with open-ended materials is one great way to foster their imagination, something they can do anything with; create, manipulate, discover, explore.
Even within areas where the information seems concrete, there is room for imagination and creativity! Enjoy the article!
http://www.cbeebies.com/za/grown-ups/the-importance-of-imagination/