The Library of Congress has put out a beautiful ebook for children : Aesop's Fables.
It is a delightful copy of 1919 book fully illustrated with clear, short text with a font that is easy to read. The illustrations are interactive - click on the frog and he will swell, click on the mouse and he will chew through the rope, etc. Better still, this ebook is available on their website or as an app for ipads or android. Make sure to get your copy so your students can read the classics like generations of Americans before them.